A bike crank is a lever arm that gives the bicycle rider a mechanical advantage when pedaling. When the rider presses their feet on the pedals, the bike crank revolves and causes rotation of the sprocket wheel, driving the chain, which in turn drives the rear wheel. Thus, a huge bending load acts on the crank in this case. Analytical models like beam theory can be used to assess the stress in such bike cranks, but it involves approximations and simplification of the problem. A structural analysis can be performed on a bike crank to obtain the strain and stress distribution on it and assess the bike crank design.
In this lesson, we will explore how to analyze the deformation that the bike crank would be subject to during normal use and learn how the weight of the rider will induce stresses inside the structure. We will prepare the model for preliminary simulations and then analyze different designs. Last, we will perform a high-fidelity simulation on the preferred design to predict how much the bike crank would deform and whether it would fail or not under the applied loads.
Download the files we will use in this lesson here.