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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 force x velocity graph is the most used tool for suspension damper analysis. This approach hides important information regarding the bleeds / spring / orifice combination. This paper describes the energy analysis, comparing two different damper suppliers, with comfort measurements using B&K Human Response Vibration Meter and MTS single channel Four Post system.

This work aims to summarize in a single form all legal requirements that dictates the minimum safety compliance required by government edicts to any wheel manufacture to have their products available for passenger or light truck vehicle in any country around the world in the year of 2016. It is not intention of this paper compare or discuss the different requirement among the countries but indicate to the manufactures of wheels what legal edicts they need to meet in case they are willing to go overseas to explore the wheel market of other country. Before start designing wheels for passenger or light truck application, any manufacture should be sure about what the government of the new market demands for wheels when installed on vehicle axis or just available as temporary spare. Another objective of this paper is to be a short reference for new automakers to know what to demand from their suppliers of wheels before starting business with them or shipping vehicles to any new market.

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.

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.

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.

Basic driveline configurations offered in mid-size trucks have a standard “open” differential. Open differentials allow smooth cornering, as the outside tire must spin faster on corners as it travels a larger arc, when compared to the inner tire. This system has a main problem when traction is lost, due to slippery roads, different friction coefficients between pavements or even when the axle is submitted to a twist ditch. All of the power goes to the wheel with the least traction and the pickup is stuck. In order to improve traction on these situations, limited slip differentials were developed. A limited-slip differential will prevent excessive power from being allocated just to one wheel, and thereby keeping both wheels in powered rotation. There are several solutions offered in the market, each one presenting different torque transfer capabilities.

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 automotive industry is continuously striving to reduce vehicle mass by reducing the mass of components including wheel bearings. A typical wheel bearing assembly is mostly steel, including both the wheel and knuckle mounting flanges. Mass optimization of the wheel hub has traditionally been accomplished by reducing the cross-sectional thickness of these components. Recently bearing suppliers have also investigated the use of alternative materials. While bearing component performance is verified through analysis and testing by the supplier, additional effects from system integration and performance over time also need to be comprehended. In a recent new vehicle architecture, the wheel bearing hub flange was reduced to optimize it for low mass. In addition, holes were added for further mass reduction. The design met all the supplier and OEM component level specifications.

The required hand wheel effort the driver inputs into the steering wheel during parking maneuvers is an important design factor for a vehicle, that has a strong influence on the customer's overall perception of steering performance. During the development of a new vehicle, the designer is faced by the challenge of achieving the desired level of steering effort without jeopardizing other handling characteristics, like steering sensitivity and on-center performance. The suspension and steering tuning to achieve the adequate trade-off between these different metrics is especially critical for manual steering systems, which is a very common configuration for emerging market vehicles. In addition, due to communization of architectures, it is common that a vehicle with a manual steering system must share common suspension components and geometric parameters with configurations that have power steering assistance, making this trade-off even more difficult.