The motion of a finite-width rimless wheel in 3D

We consider a new model for human (or biped robot) locomotion, consisting of a spoked rimless wheel of finite width rolling down a slope. In our model, consecutive spokes are on alternate sides of the wheel, and this models the finite leg separation in humans or robots. Full 3D motion is considered, in contrast to McGeer's 2D model. Numerical studies indicate that for a given slope, a single steady-state solution exists, and this corresponds to rolling straight down the slope at a particular average speed. Moreover, this equilibrium solution is asymptotically stable.