Analysis of dynamic bipedal robot walking with stick-slip transitions

This paper studies the hybrid dynamics of simple biped robot models under stick-slip transitions. Unlike most of existing works in the literature that assume sticking contact, we explore the case of insufficient friction which induces foot slippage. Numerical simulations of passive dynamic walking reveal the onset of stable periodic solutions involving stick-slip transitions. In the case of a biped with joint torques actuation, we demonstrate how one can induce and stabilize stick-slip gaits which significantly reduce the energetic cost of walking and enforce slippage even for large friction.