Design methodology for gear design of a formula one racing car: A modelling procedure based on finite element

FIA regulations for the 2015 Formula One World Championship introduced an upper limit to the number of transmission assemblies employed during the season; a new approach to reliability has been forced on the designers, along with a reconsideration of the calculation procedures. Whereas mechanical transmission reliability calculations are well coded within the commercial transportations field, the peculiar aspects of the motorsport branch - namely a) the quest for an extreme lightweight design, b) the harsh dynamic transitions in speed and torque at gear shifts with a seamless shift transmission and wheel-road chattering, c) the circumscribed consequences of a breakage due to the controlled nature of the racing track environment, and d) the frenzied design procedures pace - urged for the development of specific validation procedures, that have to be rapidly redefined with the 2015 regulation adjustment. The present contribution rethinks those reliability assessment procedures - mostly based on nonlinear, dynamic Finite Element (FE) calculations - for a Formula One gearbox. In particular, the required model complexity is discussed with respect to the inclusion of shafts, bearings and carter compliance, chassis load induced deformation, significant load case selection, misuse robustness. The finalized validation procedure is shown to be predictive with respect to the augmented reliability requirements, while remaining feasible within the motorsport timescale environment.