Stability of statically balanced stances for legged robots with compliance

Abstract

Presents a criterion for the asymptotic stance stability of a statically balanced legged robot. Typically, the static balance criterion only considers that the centre of mass is projected within the support area. This work shows that when the combined system is not stiff enough (as specified in the criterion), a so called "statically stable" stance is actually unstable. The criterion is derived analytically and also verified in experiment.