Approximate dynamic decoupling of multilimbed robotic systems

Dynamic analysis and control of robotic systems with more than a few degrees of freedom, taking into account the full dynamics of the system, is a difficult task. Thus, quite often assumptions are made to simplify the dynamics of the system. In this paper we investigate the validity of certain assumptions that result in approximate dynamic decoupling of parts of a closed chain system. Specifically, we consider robots with a star topology structure and investigate the dynamic interaction of the branches of such a robot when one or more branches are in contact or collision with the environment (thereby forming closed chains), comparing the exact and approximate dynamic models. Examples of star topology systems, where approximate dynamic decoupling can be applied, include multilegged (or bipedal) walking robots and multifingered hands.