Stiffness characteristics of new modular type antagonistic tendon-driven joint systems

This paper presents a new antagonistic tendon-driven joint (TDJ) which has an advantage of enhanced stiffness characteristics. Detailed mathematical analyses on the stiffness of typical TDJs are worked out to compare the stiffness among them. Prototypes of the proposed TDJ design are introduced in the form of packaged modular structure that merges two TDJs generating a combined roll-pitch motion or similar ones. Numerical examples are given to confirm the superior stiffness of the proposed TDJ design.