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Gear design techniques usually results on heavy drives that are contradictory to the tendency of mass reduction on the modern road vehicles applications. This paper proposes the utilization of a genetic algorithm to design and optimize geometric parameters of a transmission stage comprised of two steel gears. Although genetic algorithm is not an optimization technique on a straight sense, its use is increasing in several applications where the design space is multidimensional. In this study, the first fitness function proposed is a weighted average of critical performance factors on gears design such as total drive weight, tooth contact stress, bending stress and total space occupied by the assembly and the second fitness proposed considers the center distance influence and the tooth contact stress and bending stress. The weights of the average are modified in several simulations.

In recent years vehicle ergonomists have begun dedicating effort towards the study of human motion in the vehicle regarding moving comfort when using commands such as the steering wheel, gear shift and pedals. Correlation between subjective responses of human comfort and the maximum force achieved during the end-of-travel impact and the average slope of the force-displacement curve during the initial disengagement phase is difficult [1]. When end customers complain about clutch pedal actuation comfort, car salesmen and automakers change the entire clutch system, including pressure plate, clutch disc and clutch release bearing (CRB) to solve the problem and the suspicious root cause lies on the CRB. In most cases, previous analyses showed bearing still functional but strong contamination inside the bell housing, on the clutch and between the CRB with plastic housing and the sliding tube.

Industrial applications frequently use interference between shafts and holes to fix parts together. The present work shows the methodology for validation of Finite Element calculus for press fitting a shaft in a dust shield hole. In the case of study the dust shield can be easily hit by shocks during transport and handling of the product. The shocks would change the position of the parts and consequently the new position could become a quality problem. The process of verification determines the factors which become the project more robust using the technical of Design of Experiment (DOE). The test and the computational simulation are shown as parallel way to determine the appropriate friction coefficient which could be used to predict the assembling and disassembling force for current project as well as the new design with similar features.

Nowadays it is common for engineering applications the usage of software in parallel to test for a better understanding about some phenomena of study. The present paper intents to correlate different software and experimental practices to understand the stress state on the bearing raceway. The most important factor which determines the bearing life is the operational load. Others factors such as the stress state on the raceway due to press fit process can contribute to reduce the bearing life. A large number of factors have been studied to know the behavior of press fit. This paper, treats about the press fit and operational loading.

The synchronization system was created with the intention to make easy the gear engaging in automotive transmissions. The speed difference of the shafts is reduced during the gearshift operation by means of sliding friction of the synchronizer rings. The constant friction performance can be improved and the wear can be simultaneously reduced either by additives in the oil of the transmission or by careful selection of the friction material for the synchronizer rings. Nowadays, brass or steel meet the requirement of both friction surface and resistance on the driving lugs. The friction coefficient of the surface can be increased by scatter sintered coatings, molybdenum or carbon linings that are joined to the carrier material using complex manufacturing processes. A new concept transforms this continuous friction lining into many single friction elements that are guided by "pockets" in the synchronizer ring.