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Gearbox and driveline durability is always been a sensitive subject from both end user and manufacturer’s point of view. Since powertrain is heart of vehicle, naturally it is expected to long last and perform satisfactorily for the entire vehicle life. Sometimes the driveline aggregates especially gearbox might face some issues because of various factors, but this is distinctively noted by the driver since it is one of the important touch point of the vehicle. The gear slippage is a very typical phenomenon observed in automotive gearbox. The issue of gear slippage is very sensitive because it leads to compromising safety of the driver, also it deteriorates gear shift quality and thereby performance of the vehicle. Generally, gear slippage is not observed during end of line testing or during early kilometers of vehicle. It is observed after some thousand kilometers, that to initially gear slippage is not observed consistently and that’s why it is difficult to identify at early stage.

Success of the vehicle in the market depends on comfort provided while usage, which also include level of noise, vibration and harshness (NVH). In order to achieve good cabin comfort, the NVH levels have to be as low as possible. Powertrain is main source of NVH issues on vehicle and typically mounted on vehicle using rubber isolators. The dynamic characteristics of rubber isolators play vital role in reducing the vibrations transfer from powertrain to vehicle structure while operation and during dynamic conditions. Traditionally, isolators are manufactured using Natural Rubber (NR) to meet functional requirements which include vibration isolation and durability. At times either of above requirements has to be compromised or sacrificed due to the limitation in compounding process and other practical problems involved with manufacturing of rubber parts.

As revealed from J. D. Power surveys, today most vehicle owners consider perceived quality as a direct indicator of the vehicle build quality and durability. [5] The problem has become more prominent and noticeable in recent times, due to the desire for reduced cost, reduced weight targets, aesthetic demands, and crash requirements. The performance of the door assembly when subjected to an abuse load of sag and over opening is one such perceived quality indicator which gives the customer the first impression about the engineering and build quality of the vehicle. Door hinge inclination and hinge contact flushness tolerance are the major design parameters affecting this performance. Although these are an important design parameter, the precise quantification of the effect of these design parameters on door performance under abuse loading has remained somewhat elusive.

Durability of an exhaust system of an automobile is vital to its overall performance as well as customer satisfaction. Existing CAE approach involves simplified modelling & approximations and hence, offers a good scope to model critical details that have a definite bearing on the reliability of its prediction. In this work, an attempt has been made to capture all details such as effect of bolt pre-load on the rubber bushes/isolators, actual 3D model of the rubber bushes/isolators, material property based on measured load-deflection characteristics of the rubber bushes/isolators & contact interactions of mating surfaces that were apparently missing in the existing approach. All such modelling enhancements were incorporated in the model, which was then solved using non-linear solution technique.

The objective of this work is to develop a process that predicts the amount of steering wheel shimmy in a vehicle due to the tangential and radial force variation in the Tyre/Wheel assembly and also other components affecting shimmy. Steering wheel shimmy is defined as the torsional oscillation of the steering wheel due to excitation at the wheels. The tangential and radial force variation was modelled based on test data and applied on the wheels as excitation. Variation of these forces with the vehicle velocity was considered. The various factors that affect shimmy were then established. These factors were then divided into two categories - Geometric and Non-Geometric. A DOE was done, while considering the manufacturing variations, to study the sensitivity of those factors on shimmy. The DOE results were used to fit a regression model that predicts the shimmy velocity while considering the factors as inputs.