Formula SAE Chassis Design to Improve Suspension Tuning 2016-36-0239

In many vehicle motorsport categories, the one of the most important factors that lead a team to the victory is the suspension setup. Parameters like roll stiffness and camber changing are essential to the vehicle behavior during a driving situation. To handle these variables, features like suspension hardpoints arrangement, pivot points position and spring stiffness can be settled. However a setup only will perform a desirable effect if the chosen configuration does not change. Ideally, to make it possible, every component that holds suspension loads (suspension members, mounting plates and chassis) would have to be infinitely rigid. Even though it is not achievable, the existing deformation can be small enough to be negligible when compared with suspension displacement. In order to reach this target, this paper introduce a spring modeling and a Finite Element multibody modeling process of a Formula SAE prototype’s suspension and chassis. These models allows the investigation of chassis elasticity effect on suspension’s operation properties. Furthermore, the data obtained are essential to set the chassis torsional stiffness target and the final suspension’s pick-up points geometries, avoiding an oversized design. To validate the model a bench test was performed to obtain a correlation between the real case and Finite Element model, which reached a value of 98,2% and allowed the removal of excessive torsional stiffness and a mass reduction of 9%. In addition, the study allowed to identify a critical stress point and a reinforcement was added.