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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.

Traditional suspension tuning for ride comfort takes use of a series of physical prototype evaluations by skilled drivers, who analyze the vehicle performance in subjective terms. In this approach, the suspension components (springs, shock absorbers, bumpers, etc) are usually optimized one at a time, regardless of the consequences of the interactions among them in the global suspension behavior – this not uncommonly leads to sub optimized suspension configurations. Another problem with this approach is the fact that it is completely dependent upon physical component prototypes, whose costs and construction lead times can not be afforded in the current tight development cycles. This paper presents an objective approach that has been successfully applied at GMB, based on simulation tools, whose target is to define optimized components for the suspension without the need of physical prototypes.

As passenger vehicle design evolves and accelerates, the use of multi-body dynamics solvers has proven to be invaluable in the engineering workflow. MBD solvers allow engineers to build virtual vehicle models that can accurately simulate vehicle responses and calculate internal forces, which previously could only be assessed using physical prototype builds with hundreds of measurement transducers. Evaluation and selection of solvers within an engineering environment is inherently a multi-dimensional activity that can include ease of use, retention of previously developed expertise, accuracy, speed, and integration with existing analysis processes. We discuss here some of the challenges present in developing capability and accumulating data to support each of these criteria. Developing a pilot model that is capable of being applied to a comprehensive set of use cases, and then verifying those use cases, required significant project management activity.

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 Brazilian automotive market presents special characteristics: at the same time that it demands similar technologies applied in developed markets like USA and Europe for luxury cars, in the sub-compact entry-level segments (a segment where the profit margin is very tight) there are unique characteristics that justify the development of different cars. Taking into consideration the mini cars segment, there is no car developed specifically for the Brazilian market. While the mini cars development for the entry level segment is still rare, every new auto show presents new proposals and some of them are on the streets, but most are mainly focused in the luxury segment. These vehicles currently in the market are in a price range where it is not economically feasible for them to be acquired by someone who is coming from a motorcycle-based usage.

This work has the proposal of showing the correlation between simulation and field tests’ results for handling maneuvers for Astra and Corsa vehicle platforms. Adams was the main tool used during the modeling development and the correlation was performed for steady state maneuvers (constant radius cornering) and transient maneuvers (series of lane changes at high speed and elk test).