Design of Tensegrity-Based Manipulators: Comparison of Two Approaches to Respect a Remote Center of Motion Constraint

Abstract

Tensegrity mechanisms can offer key features such as compliance and deployability for high compactness. The absence of systematic design methods has however strongly limited their development for manipulation up to now. In this letter, we consider how tensegrity mechanisms can be designed to respect a Remote Center of Motion (RCM) constraint. Mechanisms of high compactness, respecting RCM constraint and offering compliance can indeed be of great interest in a challenging environment such as the medical context. Architectures are elaborated with two distinct design approaches, using cable- and bar-actuated Snelson crosses. Their analysis is performed, proofs of concept are built and experimentally evaluated, and their relative interest is discussed. This work brings at the same time initial results on design of tensegrity mechanisms for manipulation in a medical environment, and first guidelines to perform tensegrity mechanism synthesis.