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This study presents the comparison of vehicle handling performance results obtained using physical test tire data and a tire model developed by means of Finite Element Method. Real tires have been measured in laboratory to obtain the tire force and moment curves in terms of lateral force and align torque as function of tire slip angle and vertical force. The same tire construction has been modeled with Finite Element Method and explicit formulation to generate the force and moment response curves. Pacejka Magic Formula tire response models were then created to represent these curves from both physical and virtual tires. In the sequence, these tire response models were integrated into a virtual multibody vehicle model developed to assess handling maneuvers.

The Formula SAE competition has the purpose to stimulate the engineering students to work in teams to develop a concept, design and build small racing vehicles. In this competition, students are motivated to build a high performance car, reliable and with low development cost. The success of the team in the competition is determined with a detailed analysis of all aspects involved. Considering the frame development, some key points must be considered for the structural performance: stiffness, durability, modal and safety response. This papers focus on the stiffness analysis to verify if the frame torsional stiffness is compatible with the respective suspension for the level of performance required. The study was performed using the frame of 2012 Formula SAE from Instituto Mauá de Tecnologia using beam elements to model the frame structure in a FEA (Finite Elements Model) software to simulate the system stiffness.

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.

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.