Design and optimisation of an RTM composite bicycle crank

A prototype of the right crank was developed on the basis of a preliminary design supported by a finite element model. Its flexural and torsional stiffness performances were experimentally evaluated and compared with those of top quality commercial cranks showing the need for an improvement of the composite prototype stiffness. The FE model was then calibrated on the basis of the constituent material characterisation and the definition of suitable boundary conditions in order to achieve a reliable simulation of the experimental tests. Finally, an FE optimisation was performed to increase the crank stiffness and to investigate the influence of the elastic properties and lay-up of the composite skin on the stiffness performances.