Soft-robotic arm inspired by the octopus: II. From artificial requirements to innovative technological solutions

TLDR

Soft robotics aims to improve real‑world interaction, and octopus arms inspire this field because their pliable yet forceful limbs arise from unique muscle arrangements and tissue properties. The paper demonstrates how engineering requirements derived from octopus arm biomechanics can be applied to develop innovative soft materials, mechanisms, and actuators. The authors investigated octopus arm biomechanics to identify key principles and engineering requirements, then used those principles to design and prototype soft robotic components. Experiments show that the proposed solutions match the octopus model in compliance, elongation, and force, indicating their potential to enable a new generation of highly dexterous soft‑bodied robots.

Abstract

Soft robotics is a current focus in robotics research because of the expected capability of soft robots to better interact with real-world environments. As a point of inspiration in the development of innovative technologies in soft robotics, octopuses are particularly interesting 'animal models'. Octopus arms have unique biomechanical capabilities that combine significant pliability with the ability to exert a great deal of force, because they lack rigid structures but can change and control their degree of stiffness. The octopus arm motor capability is a result of the peculiar arrangement of its muscles and the properties of its tissues. These special abilities have been investigated by the authors in a specific study dedicated to identifying the key principles underlying these biological functions and deriving engineering requirements for robotics solutions. This paper, which is the second in a two-part series, presents how the identified requirements can be used to create innovative technological solutions, such as soft materials, mechanisms and actuators. Experiments indicate the ability of these proposed solutions to ensure the same performance as in the biological model in terms of compliance, elongation and force. These results represent useful and relevant components of innovative soft-robotic systems and suggest their potential use to create a new generation of highly dexterous, soft-bodied robots.