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This paper will focus whining noise on rear axles applied in mid-size trucks. Vehicle integration changes during development affect directly the gear noise perception, in which it may be intensified. Also, gear material and heat treatment choices for the rear axle need to be done carefully, taking into consideration the integration changes and also the driver usage. A lessons learned collection over the diverse aspects of a rear axle whining noise will be the basis of this paper.

Body in White (BIW) torsional stiffness is an important parameter for passenger vehicles, influencing its behavior regarding Noise, Vibration & Harshness (NVH), durability and handling. A BIW with high stiffness may impact mass and cost since it would be necessary to add reinforcements and/or increase thickness of the panels with more contribution for this parameter. An OEM (Original Equipment Manufacturer) may have to choose an existing platform to continue a particular vehicle family and this decision will be based on mass and costs. This work aims to study a relationship between mass and stiffness of some platforms, trying to give an auxiliary parameter to help in the OEM's decision, differentiating the stiffness of the lower (platform) and upper body.

The sheet metal joining through spot welding is the most widely used process for automotive body building, where an average vehicle has around 5,000 spot welding points in its structure. In this sense, the spot welding project is critical to the final product performance and it must be done in a way that can assure both quality and durability of the vehicle, already taking into consideration the fact that the spot weld mechanical properties related to fatigue and rupture resistance are much lower when compared to other available welding techniques like MIG welding for example. These properties have a direct impact in the fatigue durability and crashworthiness properties of the vehicle, as a significant part of the structural resistance goes through these spot welds. With this scenario, the correct application of FEA techniques is very important to assure that the projected joints and spot weld disposition meet the product targets in terms of safety and durability.

The fuel indicator float inside the fuel tank, also called just float or erroneously, fuel indicator, is in reality a fuel level sender. It is apparently a really simple part, but it consists of a small system constituted of the float itself; the float arm articulated to an axle carrying a moving contact over a resistor; and the resistor inside a housing/flange. Its function is to convert the fuel level measurements inside the tank in suitable information to the instruments in the vehicle instrument panel. Since a few years ago, it has suffered successive changes toward the objective of improving quality, durability, reliability and performance, or even motivated by innovations in the installation environment and correlated systems, such as, emission controls, affecting the tank internal space, and highly corrosive type fuels.

1 During the development of a new clutch disc damping system and after three months of hard work the engineering team got stuck with unsatisfactory system performance (rattle noise), despite the help of a computer simulation software. The only alternative seemed to be using a more expensive damping concept but, besides the fact that there wasn't much development time left, that option would increase part cost by unacceptable US$ 200, plus development cost. The team then decided to try Taguchi's Robust Engineering optimization approach for the first time. In just two weeks the authors got a 4.6 dB gain on the signal-to-noise ratio. That allowed us to keep the initially proposed system, thus avoiding the cost increase. Besides, the authors were able to keep the development schedule on track.

This paper came from the latent needs of the Brazilian Market for products more robust and at the same time cheaper. With these needs in mind the product development team of General Motors do Brasil have developed together with Altair Engineering do Brasil a design methodology based on the topologic optimization technology. The objective of this paper was defined in a meeting of the technical teams of the two companies: Develop the application of the topologic optimization technology on design of structural components using actual GMB models. This methodology is described on this paper with some practical examples where it was applied. One the important news here presented it was considering the casting constrains that leave to an optimal design that can be produced. The results here presented were obtained using optimization and compared with the traditional approach here defined as try-error.

The existent competitiveness in the automobile industry has been taking their manufacturers to an incessant search for methods and processes that seek the production of vehicles with quality and accessible costs to their costumers. The Vehicle Development Process (VDP) became an essential element for the success of a vehicle in the market, because the companies found out that, when concentrating their efforts during the development phase, the opportunities for product improvement will be much less onerous when compared with the costs spent when the vehicle are already in production. On the other hand, those improvement opportunities are evidently more difficult of be pointed during VDP than when the vehicle is already in production. This article aims to evaluate how the Design for Six Sigma (DFSS) methodology can be applied to the vehicle development process in order to provide significant results in terms of quality improvement, cost optimization and reduction of development timing.