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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.

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.

Few products or services exist that do not require some supply chain management. The more suppliers that are involved the more complex the supply chain management becomes. Even if the entire supply chain from basic raw materials that come from the earth or out of the minds and actions of people, is not considered there is still a supply chain that must be attended and in today's global economy competition is growing every day, and automotive products (vehicles and components) are often developed in one country though it's made based on global architectures, used and applied in other markets, and to find success in this competitive reality, automakers and/or global business migrated from local suppliers to global sourcing and in today's world of global outsourcing, supply chain management plays an ever important, strategic and expanding role in delivering results once automakers are aiming to launch low cost vehicles and recognized as world best-in-class products.

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.

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.

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 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].

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 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.

Vehicle ergonomics, more specifically driver ergonomics, has been the subject of interest in the automotive industry as a way to provide customers vehicles that have more than modern project, efficiency and competitive price. The driver ergonomics is related to the way the driver interacts with the vehicle interior, particularly, with the seat, hand and foot controls, considering aspects such as ease of access, space, proper upper and lower limb motion and drivers comfort and fatigue. Regarding the lower limbs, the driver’s comfort can be evaluated in terms of joint moments and muscle forces, which are influenced by the hip, knee and ankle joint angles, which in turn depend on the distances between the seat and pedal. Variations in seat to pedal horizontal or vertical distances will result in different angular positions and, consequently, different joint moments and muscle forces, which are associated to greater or lower muscular activations and greater or lower driver’s fatigue.

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 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.