Jennifer Kotzin with Gary Chottiner

Modeling Shimmy on Bicycles

In bicycling and motorcycling, there are times in which the headtube and steerer begin to oscillate, often strongly enough to throw the rider or force a crash. Those who have experienced it have nicknamed this effect the ‘Death Wobble’. This project will be done in two parts. The first is to take existing simple mathematical models of bicycle stability and expand upon them to include a more comprehensive set of factors. Possible causes of the shimmy that are currently described in the literature include total mass and total speed as well as the weight distribution. This project will initially focus on weight distribution and the structure of the bicycle frame itself. The mathematical model and simulations will be refined by testing their predictions on a bicycle, taking suitable safety precautions.