Inflated Bendable Eversion Cantilever Mechanism with Inner Skeleton for Increased Payload Holding

TL;DR

This paper introduces a novel inflatable mechanism with an inner skeleton that enhances payload capacity while maintaining flexibility, enabling applications like extended robots and wearable mechanisms.

Contribution

The study presents a new design combining a multi-joint skeleton with inflatable membranes to improve load capacity without sacrificing shape and compliance.

Findings

Payload increased compared to membrane-only structures

Design method for rigid articulated links developed

Mechanism capable of shape fixation and bending

Abstract

Inflatable structures used in soft robotics applications exhibit unique characteristics. In particular, the tip-extension structure, which grows from the tip, can grow without friction against the environment. However, these inflatable structures are inferior to rigid mechanisms in terms of their load-bearing capacity. The stiffness of the tip-extension structure can be increased by pressurization, but the structure cannot maintain its curved shape and compliance. In this study, we proposed a mechanism that combines a skeleton structure consisting of multi-joint links with functions to increase rigidity while keeping low pressure and realizing the functions of bending and shape fixation. We devised a design method for rigid articulated links and combined it with a membrane structure that utilizes the advantages of the tip-extension structure. The experimental results show that the payload of the designed structure increases compared to that of the membrane-only structure. The findings of this research can be applied to long robots that can be extended in the air without drooping and to mechanisms that can wrap around the human body.