Tendon-Driven Hyper-Redundant Manipulators: A Review on Design Solutions

Due to their uniqueness, hyper-redundant manipulators are becoming increasingly relevant in robotics research. The abundance of degrees of freedom makes them adaptable to a variety of applications across various fields, including inspection, medical procedures, and space exploration. These manipulators are particularly effective where high maneuverability is needed, particularly in constrained environments, thanks to their surplus of degrees of freedom. While this hyper-redundancy offers significant benefits, it also introduces complexities in developing effective actuation strategies and innovative design solutions. This work is the first of two parts of a survey conducted on hyper-redundant manipulators, their design, and actuation strategies. This first part of the review provides an examination of the current state of tendon-driven hyper-redundant manipulator design and actuation, analyzing both continuum and rigid-link manipulators. The article synthesizes recent advancements, explores various designs, and identifies key challenges.