317396.fig.003
Figure 3: Rotation of CG around the edge of the supporting polygon under the influence of external disturbance for robot standing in an arbitrary posture. are footholds, and are their projections on a horizontal plane. is input velocity, created by external disturbance energy , and is robot’s body velocity. is the plane of CG rotation around , and is a vertical plane of an unstable equilibrium above . Other variables are defined in Section 3.