Bicycle Mechanics and Dynamics
New! "A bicycle can be self-stable without
gyroscopic or caster effects",
Science Magazine, April 15, 2011.
Cornell bicycle research began in 1985 when Jim Papadopoulos came to Cornell to work with Andy Ruina, or vice versa. Undergraduate projects have included the application of constraints to pedals, making a geared unicycle, designing a new suspension, measuring the efficiency of a bicycle transmission, designing a constrained pedal, tests of stability, automatic wheel truing, tests of what people can perceive, measurement of the effect of inertia on pedaling efficiency, etc.. Bike research had a lull from about 1988-2002. Starting in 2002-03, with the visit of Arend Schwab
from Delft, collaborating with graduate student Andrew Dressel, the stability research has progressed.
Demonstration (MP4 video) (3 MB)
The clearly-observable asymptotic stability (quickly decaying oscillations) of a bicycle is shown.
This is a random bicycle. The aymptotic stability of this bicycle is predicted by the equations of motion of an ideal conservative bicycle (with disk wheels and point contact).
A program for calculating stability eigenvalues (JBike6).