Lateral Dynamics and Stability of the Skateboard

The natural lateral dynamic behavior of a skateboard is described in the absence of rider control. The effects of vehicle and rider parameters are investigated and stability criteria are derived in terms of these parameters. It is shown that for certain parameter values a simple one-degree-of-freedom vehicle model predicts a critical speed above which inertia effects can stabilize the roll motion, and that the frequency of roll oscillations is a function of forward speed. A more complicated two-degree-of-freedom vehicle model, including independent roll of both the board and of the rider, is also derived and is shown to have the possibility of speed stabilization as well. Experimental validation of the first theory is included.