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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 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.

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.

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.

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.

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.

Microphone array based techniques have a growing range of applications in the vehicle development process. This paper evaluates the use of Spherical Beamforming (SB) to investigate the transmission of wind-generated noise into the passenger cabin, as one of the alternative ways to perform in-vehicle troubleshooting and design optimization. On track measurements at dominant wind noise conditions are taken with the spherical microphone array positioned at the front passenger head location. Experimental diligence and careful processing necessary to enable concise conclusions are briefly described. The application of Spherical Harmonics Angularly Resolved Pressure (SHARP) and the Filter-And-Sum (FAS) algorithms is compared. Data analysis variables, run-to-run repeatability and system capability to identify design modifications are studied.

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.

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

Product Design is a process of creating new product by an organization or business entity for its customer. Being part of a stage in a product life cycle, it is very important that the highest level of effort is being put in the stage. The Design for Six Sigma (DFSS) methodology consists of a collection of tools, needs-gathering, engineering, statistical methods, and best practices that find use in product development. DFSS has the objective of determining the needs of customers and the business, and driving those needs into the product solution so created. In this paper the DFSS methodology is employed to develop the optimal solution to enhance sound transmission loss in a vehicle front of dash pass-through. An integrated approach using acoustic holography and beamforming Noise Source Identification (NSI) techniques is presented as a manner to improve sound insulation during vehicle development.

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.

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 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.

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.

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.

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.

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 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.

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.