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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.

This article is the sintezis of vehicle development process, starting from its characteristics and included in a competitive market, and shows the dimensional optimization process application and validation using the GD&T by ASME 14.5 M. INDEX KEY WORDS INTRODUTION TECHNICAL GROUNDING STUDY EXAMPLE CHOICE PROCESS STUDY EXAMPLE APPLYING AND VALIDATING GD&T BY ASME 14.5M STANDARD STUDY EXAMPLE RESULTS FINAL CONSIDERATION APPENDIX BIBLIOGRAPHY

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.

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.

In a growing global environment, new products development demands balancing regional requirements and resources in the proposed solutions targeting optimal results. The interaction between Development Centers must pursue, following clearly defined rules, proposals that consider factors from all involved regions. This paper proposes description of important aspects to be considered in Car Suspension Global Product Developments.

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].

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.

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.

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.

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.

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.

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.

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.