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Today, the interior noise perceived by the occupants is becoming an important factor driving the design standards for the design of most of the interior assemblies in an automotive vehicle. Buzz, Squeak and Rattle (BSR) is a major contributor towards the perceived noise of annoyance to the vehicle occupants. An automotive vehicle consists of many assemblies such as instrumentation panel, doors, sun/moon-roof, deck lids, hood, etc. which are the potential sources of BSR noise. The potential locations of critical BSR noise could be contained within such assemblies as well as across their boundaries. An extensive study is made regarding the overall structural behavior as well as their interaction under typical road loads to come up with enhanced design for improved quality from the BSR noise perspective. The alternative designs were comparatively evaluated for their relative noise level from buzz, squeak and rattle perspective using an analytical tool - N-hance.BSR.

Structural durability is one of the key factors in determining the robustness of a product having a direct bearing on customer perception of quality and reliability in passenger vehicles, and is one of the major factors affecting customer loyalty. It is recognized that significant fatigue failures occur at spot welds in an automobile body structure, and accordingly various methods are adapted in the industry to predict such failures. However, most of them follow the traditional fatigue and fracture analyses, which are computationally challenging, expensive as well as mathematically complex to apply on a full vehicle system. As a result, most of these methods depend on iterative solutions e.g. Design of Experiments.

Structural dynamic characteristics such as fundamental structural modes and the corresponding frequencies are the most important factors in determining the robustness of a product design. Vehicle vibrations have a direct bearing on customer perception of quality, comfort and reliability in passenger vehicles, and play a key role in retaining customer loyalty. The conventional wisdom to enhance the fundamental frequencies of a vehicle is to optimize the body structure for the best stiffness-compliance combination for a given vehicle line. In the process, considerable mass is often added to the body-in-prime structure for enhancing the structural frequencies by about 0.5-1.0 Hz. On the other hand, the process is often technically challenging involving complex computational methods and software for optimization, and requires a priori knowledge of every component of the product regarding its influence on the overall dynamic performance of the structure.

Better dynamic characteristics and longer fatigue life implies a robust product which has a direct bearing on customer perception of quality in passenger vehicles, and is one of the major factors affecting customer loyalty. Traditional optimization of dynamic characteristics is first performed to improve fundamental bending and torsion frequencies of automotive body structures. Such analyses typically involve mass minimization for which gage sensitivities are used to identify critical parts. It is recognized that most fatigue failures in an automobile body structure occur at spot welds, and almost none of the traditional optimization methods include the influence of spot weld layout on dynamic characteristics and durability. Also, load path identification tools currently available are not very effective for large & complicated parts such as body panels, floor panels, etc. since typically only small regions of such parts absorb energy.