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Side Door Closing Sound Quality is one of the first impressions a potential customer has about a vehicle. It can enhance an impression of robust and high quality vehicle. This paper is a study of Side Door Closing Sound of a specific vehicle model. The main objective is to understand how Door Closing Sound Quality varies over several vehicles samples and how to improve the design and/or production process in order to achieve better Sound Quality. Two vehicles (same model) with distinct performance have been chosen among several samples. Both have been evaluated and the physical differences are weighted to realize what really matter for Door Closing Sound Quality.

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.

In the last decades, there has been an increasing demand for vehicle noise control and, at the same time, fuel economy has become critical for the automotive industry. Therefore, a precise balance between performance and mass of sound package components is essential. In this work the original dash insulation system of an automotive vehicle was replaced by a lightweight alternative. The methodology of Statistical Energy Analysis (SEA) was employed to design multilayered fibrous constructions for engine noise control. The results were verified through experimental testing and supported the achievement of vehicle requirements regarding comfort, weight and environment.

Development of an Electrical Power Steering (EPS) system for Emergent Markets, with emphasis on improved fuel economy and cost advantages to the customer. The EPS for Emergent Markets provides high steering wheel assistance on parking maneuvers and appropriate assistance on driving conditions similar to conventional EPS systems. The assistance levels decreases while vehicle speed increases providing better steering feel at high speed conditions (highway tracks). It also provides good tuning capability balanced with piece cost. In addition, this EPS enables an aftermarket bolt-on system for non-assisted steering vehicles (i.e., manual steering vehicles).

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.

Noise generated during tire/road interaction has significant impact on the acoustic comfort of a vehicle. One of the most common approaches to attenuate road noise levels consists on the addition of mass treatments to the vehicle panels. However, the acoustic performance of sealing elements is also relevant and has an important contribution to the noise transmission into the vehicle interior. In this paper the correct balance between the mass added to treat vehicle panels and sealing content is investigated. The procedure to quantify the critical road noise transmission paths consists of recording interior noise levels as applied treatment is removed from potential weak areas, such as wheelhouses, floor, doors and body pillars. It is observed that the noise propagation through body pillars has a direct influence on road noise levels.

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 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 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.

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.

In this paper an alternative engineering solution to control vehicle steering wheel vibration is presented. The strategy is focused on the implementation of an effective tuned vibration absorber which also complies with time frame and costs requisites. The vibration levels in this case study are enhanced due resonances in the chassis frame and steering column. The tuned mass damper is basically a suspended mass attached on a vulcanized rubber body, aiming for the customer benefits; this solution can be classified as low cost as well low complexity for implementation. In this case study, a mid-size truck was used as a physical hardware and the data were collected through accelerometers on the steering wheel and other critical components. As a control factor, different tunings on different parts were applied to optimize the auxiliary system performance and robustness.

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.

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.

Manual steering is largely employed on emergent markets and it demands high level performance to be competitive. To achieve customer satisfaction, it is important to understand physically and be able to quantify what is good performance regarding imperative steering aspects. Nevertheless, global projects and quality management require objective measurements and reference numbers. The strategy defining the measurements in order to compare among development steps and benchmark must be studied carefully. Objective measurements and subjective evaluation correlation is necessary to define the reference data. In this project, several cars were evaluated and measured performing standard maneuvers. The maneuvers were performed to obtain appropriated and enough information to understand the performance and to do the correlation. The subjective evaluation was normalized and; using objective data, parameters were calculated to represent properly and in a robust form the driver fills.

The control of noise and vibrations using conventional damping materials is typically associated to mass penalties in a vehicle. A lightweight alternative employs piezoceramic materials connected in series to a resistor and an inductor (R-L circuit) to perform as mechanical vibration absorber, called piezoelectric resonator. In this paper, piezoelectric resonators are designed to attenuate vibration in a vehicle panel. The choice of design parameters, such as correct placement for the piezoelectric patches and the optimal electrical circuit values, is assisted by Finite Element simulation (FE) and theoretical analysis. Measurements of Sound Transmission Loss (STL) and modal analyses are conducted to demonstrate the efficiency of the proposed technique when compared to a conventional damping material.

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.

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.

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.

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

Over recent years, demands for fuel-efficient vehicles have increased with the rise of the fuel price and public concerns on environment. Recently, application of lightweight materials is increasing in the automobile industry in order to improve mass reduction and consequently fuel efficiency. On this particular study, with a goal of developing a Lightweight Fixed Steering Column, it was identified an opportunity to replace fixed steering column metallic upper and lower brackets by polymeric material. In order to fulfill NVH, Crash, Durability and Performance requirements, a DFSS methodology has been applied. As a result, It was achieved ∼51% of mass reduction, ∼10% of performance improvement with ∼14% of cost increase.