Projeto de cinemática e análise dinâmica de sistema de suspensão para um protótipo do tipo fórmula SAE

Abstract

During the increase of the Formula SAE category, a request to consider the vehicle movement behavior during design process emerged, with the purpose of observe the efforts input into sprung masses, predict performance parameters and anticipate its attitude into severe track conditions. Therefore, the present work has the main objective to design a suspension system considering selection and characterization of the tire, in order to pre-select geometrical parameters of the system performance and verify, on track conditions, the influences of the setup variation for damping ratio and tire stiffness. Throughout the predefinition of geometrical variables, spatial points of double wishbone system were defined to obtain better values of tire contact with ground, steer travel and car packaging. Subsequently, a computational model with seven degrees of freedom (full car model) was developed to analyze configurations response on three critical conditions: transient-state cornering, chicane and slalom. In comparison with previous car, the new suspension hardpoints allowed small range of curvature radius, more contact between tire and ground and small forces and moments to steer the front wheels. The ride analysis enabled observations of the vertical response on the three critical conditions, conclusions of the correlation between stability and vertical response, characterization of transient stability index profile, investigations and suggestions of useful setup to each maneuver and dynamic event into Formula SAE competition.