Stability Analysis of a Planar Wire-Driven Continuum Robot

Abstract

This paper discusses the stability of a planar wire-driven continuum robot, including the deformation of the backbone into a shape with inflections in one segment. Two types of wire constraint condition by actuators were considered. One is the condition where wire tensions are kept to be the desired ones and the other is the condition where wire lengths are kept to be the desired ones. The desired ones above were obtained as the solutions of the inverse analysis for the target position and orientation. For both wire constraints, total potential energy of a continuum robot was formulated. Then the sufficient conditions were derived for the equilibrium to be the strict local minimum of the total potential energy. Through the numerical calculation, it was found that the stability was higher in the one where the wire lengths were kept than in the one where the wire tensions were kept.