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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.

Door Closing Effort is one of the first impressions a potential customer has about a vehicle. The energy someone needs to give out to push and lock a side door vehicle is easily felt and can enhance the impression of a robust and high quality design vehicle. In other words, Door Closing Effort is one of the issues manufacturers shall look over in order to achieve perfect levels of Human Vehicle Integration (HVI). The aim of this paper is to present a case study of Side Door Closing Effort of a specific Hummer vehicle. It will be shown how door closing effort varies according to several parameters, and how to improve the design and/or production process in view of achieving better effort levels, considering the Hummer case as a background. Several variables that influence on the overall energy of this process have been evaluated, and the physical differences were weighted to demonstrate what really counts for reaching a comfortable level of Door Closing Effort.

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.

This work conducted an optimization in sheet metal blank's sizes for cold pressing automotive parts, comparing dimensional characteristics of automotive hood outer panels deep drawn with commonly used blank sizes for this process. As a result, it was possible to suggest modifications to smaller blank sizes, accordingly to the improvement accomplished in this work. The experimental study was conducted from observations in part's superficial aspects after its deep drawing process, which was realized in a commonly used tooling for automotive industry, with a blank's width reduction for the suggested case. The results showed a cost reduction opportunity based in this optimization.

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.

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.

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.

Brazil, that presents one of the highest accidents indexes of the world, does not have any specific regulation related to the use of an external light during the day time which provides a better visibility of the vehicle in movement and according to studies gives more reaction time for the other road users. Many countries in Europe and North America shows good results since they adopted the lights on during the day with collision reduction of vehicle to vehicle, vehicle to pedestrian and vehicle to cyclists. The aim of this study is to show the benefits of the Daytime Running Lights (DRL) and its relation to the reduction of the traffic accidents, as well as a brief analysis on the use of a dedicated system, which can be more efficient since it can be designed to provide a light distribution allowing a better visibility as possible.

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.

Test Protocols for pedestrian head protection in a car pedestrian accident have been discussed for several Technical Communities in order to identify ideal boundary test conditions to evaluate injury limits. With the purpose to harmonize with final Global Technical Regulation 9 for Pedestrian Protection published by ECE in January 2009, European New Car Assessment Program (ENCAP) has changed their Child and Adult headform weight and geometry boundary test conditions. However 5 Kph remains as difference between both protocols. This work presents a comparative head impact test analysis for both headform at ENCAP and GTR#9 boundary test conditions when performed at critical bonnet regions.

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.

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 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.

In the current automotive industry, in an increasingly challenging environment due to strong competition, to develop a product that performs its functions objectively, with quality and mainly with the lowest possible cost, these are the keys to conquer competitive advantage. This paper is intended to explore cost reduction of an automotive system by using the techniques of the methodology EV / AV (Engineering Value / Analysis Value). The analysis are framed as exploratory, in the form of study, with ratings of the components and their functions, followed by the generation of ideas with the completion of an indication of a great potential for a product development with optimized cost.

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 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.