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Analytical models are very useful to the vehicle dynamics project engineer in order to provide simple solutions that bring at the same time a deep understanding of the physical phenomena being studied. Due to their structure, the input of analytical models are only the variables of interest affecting the concerned handling metrics - this fact reduce the parameters quantity to build the same model, making them proper choices for advanced studies. Additionally, analytical models are more efficient in computational terms, aspect convenient for studies that involve large amounts of calculation iterations like numerical optimization processes. This paper presents analytical model results for the roll gradient, understeer gradient and steering sensitivity metrics and proposes enhancements in order to obtain results with accuracy compatible to the experimental measured variables.

This paper presents the results of a study about the influence of the suspension manufacturing and assembly induced dimensional variation on the vehicle dynamic behavior for a compound crank rear suspension. A selection of representative vehicle dynamics metrics has been considered for this assessment and each individual dimensional variation has been categorized with respect to its overall effects on the selected metrics. By doing this, it is possible to identify the critical points where the dynamic behavior of the vehicle is more sensitive to the resulting dimensional variation, therefore creating a new criteria to define the appropriate tolerance control for the manufacturing and assembly of the related parts.

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.

The automotive industry demands for quality and technological innovations that enhance the performance of their products. Visual quality and corrosion resistance are also very important, even for fasteners exposed to the weathering throughout its life cycle that shall meet the performance requirements specified by the automotive industry. This paper shows how the search for new technologies leads to innovations in the already established surface treatment with a new generation of sealers for the automotive industry. This brand new technology of organic/polymeric sealer applies in water basis a single and uniform layer with low molecular weight (1000 to 10000 Dalton) in order to enhance specific properties such as high corrosion resistance, low coefficient of friction attributing characteristics of self-lubricating surface and increase in the wear resistance of the coating.

This paper explains the evolution of Electric and Hybrid propulsion system from its early beginning and the drawbacks faced along the way, explaining why the Internal Combustion Engine turned out to be dominant and the reasons why the fossil fuel model is now in question. It explains the recent developments that allowed its production and the progressive electrification steps leading from conventional Internal Combustion Technology towards the top electrification technologies. It demonstrates how some old-fashioned technologies are reinvented in order to boost performance and efficiency on Hybrid Propulsion systems. The paper explains the evolution on the Hybrid Propulsion Systems architecture in the last 20 years and how it brought a considerable improvement on efficiency and performance leading to the highly advanced hybrid vehicles now in production. It also points out to future new developments on the sector.

For high CG passenger vehicles the body control is a very important parameters for customer perception. The compromise between cornering (body roll) and uneven road (head toss) is the main goal. This paper describes how dampers, spring rate and anti roll bar can influence the desired compromise. Single channel Four Post system and vehicle dynamics measurements give the necessary support for this analysis.

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.

General Motors Corporation has always made every effort so that our end products and processes and configuration of components could help preserve the environment. Along those lines, General Motors do Brasil started to develop a protective coating that is corrosion resistant and environment friendly. At first, this will be used for fasteners. This effort involves dramatic changes in attitude, such as our need to admit that we are responsible for managing resources and keeping our world habitable and healthy for the future generations. This study describes metallic and organometallic coatings with an increased resistance to corrosion associated to temperature, free of such harmful metals as cadmium, nickel, lead, chromium, etc. Also demonstrated here is the significance of the total friction coefficient and its composition, considering the friction coefficients inherent to the fastener threads/heads.