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This paper proposes a elaboration of a Fault Tree Analysis (FTA) for gearboxes to study reliability of statistical models more adequate for components which may be able to generate failures. Therefore there was generated a fault tree with scale and shape factors for each component. Once obtained the statistical models for each failure, a study about critical levels of the system components will be valid by reduction of the FTA models. The aim of the actions in relation to the improvements will increase the reliability of the gearboxes. This method can be applied in various vehicles systems allowing a complete statistic modeling. Thus, a general map of the product can be made, in which there are components that generate or will be able to generate failures in specific kilometer. With this, it is possible to obtain a model for management of the actions of warranty and descriptions for the areas of product development and manufacturing.

This work presents an application of the simulated annealing algorithm to redundant system reliability optimization, and its objective is to analyze this method and compare to other optimization methods, which are Genetic Algorithm, Evolution Strategy and Lagrange Multipliers. A hidrid optimization algorithm, composed by Simulated Annealing and Genetic Algorithm, is also developed in this work, to conciliate the advantages of both methods. The results presented by the Simulated Annealing and the hybrid algorithm are significant and validate these methods as robust tools for parameters optimization in engineering systems developments

The development area of the bearing's industry constantly searches for a better efficiency and a lower film oil thickness in surfaces with high roughness under relative motion. In these cases, operational conditions like high loads and temperatures, as well as low safety margins for weight and size, considering the lubricant viscosity, should be taken into account as fundamental design parameters. In order to know better the elastohydrodinamic lubrication effect, firstly, it is necessary to understand deeply and accurately the applied loads on the ball element bearings. For this purpose, the accurate analysis and study of the performance of these machine components is carried out, using analytical methods and giving special focus on the velocities and accelerations involved, as well as different types of loads applied on the ball element and their distribution and consequences during the ball motion inside the bearing rings.

The finite element method (FEM) can be used as an analysis tool in automotive electromagnetic engineering and recently new technologies such as Domain Decomposition Method (DDM) were employed to simulate very large field structures such as a whole vehicle. A FEM solver offers numerous advantages over other numerical methods, such as method of moments (MoM) and finite difference time domain (FDTD), because it has the ability to handle complex heterogeneous and anisotropic materials which is often used inside vehicles, also providing a very precise representation of complex geometries via high order tetrahedral elements. Nevertheless, for large field problems such as the scenario of the ISO 11451-2 where an antenna radiates a vehicle in an anechoic chamber, FEM solvers requires an interface between an infinite domain to a finite domain through the use of radiating boundary conditions on artificial truncation surfaces. This causes the solver to model a great quantity of air regio.

One traditional solution to start an internal combustion engine is the starter motor. Since its conception little was changed in its operational dynamics, even after passing by several design optimization processes. This fact elapses from the absence of application of an analysis tool capable to express the existing relations between its subgroups and the functions that these play. The main goal of the present work is to get a complete mapping of all the functions, components and flows of information and energy, through the application of an existing methodology of analysis, known for “function structure technique”, on the described product. Therefore, this mapping will supply a better understanding of the product architecture. First of all, the composed system for the starter motor is divided hierarchically in subsystems according to the existing assemblies. The operation chain is then separated through static and dynamic inspections during its use in the combustion engine.

Had to the development of new projects of vehicles more economic as for example, the hybrid vehicles, have become bigger investments in transmission systems mechanics more adjusted. Thus being the increasing market of the continuously changeable transmissions it demands that its characteristics of performance fully are known and constantly developed. Of the some existing constructive types one initially opted to the modeling of the system of pulleys of changeable diameter and leather strap. To leave of this modeling one became alterations of some components and verified the behavior of this CVT in a simulation of passage of a vehicle. This passage was drawn so that the vehicle more faced daily situations of a vehicle considered in a track accented, that requested of the transmission the reactions boundary lines that supplied to torque and power of enough engine, or, so that the vehicle executed the passage, a not to leave of the limitations of the system and the CVT.

Due to changes in competitiveness attributes, consequence direct of technology development, new markets and customer profile, it has been required continuous improvement in the tools and methodologies of Quality and Productivity management to maintain the organization's health. These are new requirements for project managers that facing the challengers in the 21st Century in Automotive Industry. The Lean Manufacturing was a great innovation in this area because improve the organizations profitability, which is necessary for they survive in the competitive new scenarios that we are currently confronting. Allied with these new constraint conditions, the Six Sigma Methodology helps the organizations to improve the Value Add within the business process and to avoid wastes, which are responsible for lack of focus, increase of process costs, decrease of customer satisfaction and consequently lack of competitiveness.

The dependence among the components and the data associated with a repair politic, that can consists of the number of available teams and the components repair priority, rarely evaluate the measures of reliability. Thus, to evalute the reliability and availability values with these conditions, this article develops a methodology using the theory of Markovian stochastic processes. A system of ordinary differential equations is obtained using the concepts of component failure and repair rates, constants or variable in the time. Solving it, these values are obtained, allowing the calculation of the MTTF of the analyzed system, for an allowed error.

This paper discusses some aspects of durability tests in laboratory, justifying the necessity of a new procedure for data compression. Attention is paid to dynamic tests, with the presence of inertia forces. The new procedure is introduced, which uses concepts of fatigue due to vibration and signal analysis. The compression procedure is applied to generate a synthetic signal for the experimental stress test of an automotive component.

The reliability optimization of redundant systems aims to improve some design parameters as reliability or cost, using optimization methods, in order to determine the optimum number of redundancies in each component of the system. This work compares some optimization methods (Lagrange Multipliers, Evolution Strategy and Genetic Algorithm) and its objective is to determine which method is more adjusted to the problem.