Rear Wheel Steer Bikes

Abstract

The design of the ordinary bicycle has barely changed since the end of the 19th century. Until then it evolved to a well ridable machine with no need for further drastic modifications. However, around 2011 it was shown that, just like an ordinary bicycle, strange appearing designs could also be stable. One of these designs was a bicycle that steers with the rear wheel instead of the conventional front wheel steering. This was contrary to the popular believe that such a bicycle is inherently unstable. Although it was seen that such a bicycle could be stable, both from a theoretical as well as an experimental point of view, it was not yet revealed why and how this occurs. Now, a thorough study on the stability of rear wheel steered bicycles is conducted to fill up this knowledge gap.

The history of research on rear wheel steered bicycles varying from simple trial-and-error studies, to theoretical researches based on models, is researched and documented. This makes clear where the knowledge on the subject can still be increased and which methods could be used to do that. Subsequently, these deficiencies in the knowledge on rear wheel steering for bicycles are investigated. With the Whipple bicycle model, a quantitative kinematic steer-side definition is found and rear wheel steering is dynamically compared to front wheel steering on bicycles. In this process differences and similarities between the lateral dynamics of different vehicles like bicycles, cars or unicycles are mentioned. Finally,
the process of modeling, designing, constructing and validating a self-stable rear wheel steered bicycle is revealed.