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Nowadays the automotive market is reducing product development time and launching more technological vehicles, always focusing on having even more safety with better customer experience which generates big competitiveness and requires more accurate and faster development, the virtual simulations make it possible to meet this new reality with a high confidence level. This work comprises the validation of a methodology to analyze the design confidence level for flexibles associated with suspension kinematics. To validate the methodology, the scanned physical model was compared with the virtual simulations using the Simcenter 3D Flexible Pipe software. As inputs data for simulation, it is used geometrical, physical, and chemical information. Through the suspension kinematics study was establish possible movement situations to obtain the flexibles deformations attending to all suspension positions.

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 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 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.

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.

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.

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

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.

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].

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.

Style changes and technological advances have led to reduced service life of current products as automobiles. These are among the goods that are constantly re-designed to meet our growing needs for improved products. However, these demands for new products and more modern has meant a great cost to our natural resources, such as excessive use of raw materials, water and energy during production, use and end of life cycle of these assets. The increasing scarcity of land available for the proper disposal of waste in landfills, in addition to the high cost of implementing these areas and the increasing distances to urban centers imply the need to reduce solid waste generation, including here the automotive. The growth of the automotive market has created a serious problem due to the disposal of urban waste volumes generated, the great diversity of materials involved and their toxicity.

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.

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.

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).

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.