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The challenge to find optimal solutions regarding energy efficiency in vehicle systems such as transmissions, engine and chassis involves the understanding of friction torque, friction losses and loading conditions interactions. Design variables such as internal dimensions, component profile and roughness will lead to a final component from which needs input energy to start and maintain movement. Even a component without load requires a minimal amount of energy and assembled in a vehicle will contribute to fuel consumption and emissions. The same component over loading conditions will turn these values higher due to the energy balance. Using engineering modeling techniques, the loading conditions, such as radial forces and rotation speed were implemented by parametric analysis and a dynamic model was built to obtain the variable contribution in energy-based design.

To overcome the proposals concerning to the reduction of the fuel consumption and gases emissions required by the regulatory councils around the world, but also required by the actual market, since economic vehicles have been more valorized than ever, the automotive industry have dispended considerable efforts in the development of new technologies, such as hybrid cars, and in the improvement of the current projects. Friction of any magnitude retards the motion and results in energy loss, causes temperature increase and should be reduced in order to improve the system efficiency. This paper intends, by means of analytical calculation based on dynamic systems and comparisons with Finite Elements Analysis, propose a robust method to analyze friction losses in automotive mechanical systems. Transmission application was chosen to conduct this analysis.

This paper presents a standardization model for the analysis of rolling bearings in transmission systems. A procedure was applied to assist gearbox prototype development. A solid methodology with robust software, based on international standards, allowed the development engineers to shorten simulation time. In this case, the calculations were performed taking into account system elasticity, which resulted in an exact calculation of the internal load distribution in the bearing, including contact pressure, tilted position and with rolling element profile, considering effects of lubrication conditions and contamination. The program also evaluates the resulting forces of gears, displacement, shaft deflection, contact pressure, stresses, torsion and inclination of the shafts. All the information processed aims at providing safe design, optimal solution and cost impact.