Bicycle Pitch-over Reconstruction Analysis

During a pitch-over event, the forward momentum of the combined bicycle and rider is suddenly impeded at the front tire and front axle causing the rider and bicycle to rotate about the bicycle front structures and also possibly propelling the rider forward. A pitch-over event can result in significant injuries to the rider. This paper presents the examination of the pitch-over of a bicycle by approaching the event using two different methods over what has been published previously. One method uses Newton’s 2nd Law directly and the other method uses the principle of impulse and momentum, the integrated form of Newton’s 2nd Law. The two methods provide useful equations, contributing to current literature on the topic of reconstructing and analyzing bicycle pitch-over incidents. The analysis is supplemented with Madymo simulation models to evaluate the kinematics and kinetics of the bicycle and rider interacting with front wheel obstructions of different heights. The effect of variables such as rider weight, rider coupling to the bicycle, bicycle speed, and obstruction height on resulting kinematics were evaluated. The analysis shows that a larger momentum requires a higher obstruction to arrest that momentum and result in a pitch-over event. The Madymo findings are cross-correlated to the predicted kinematics from the two numerical methods. These models provide analytical tools when Madymo software is not available. Validation of these models is explored using Madymo.