Wearable power-assisted robots driven by artificial rubber muscles should be designed with a wide range of assistance capabilities to support various tasks while minimizing the sense of restraint when worn. Ideally, to realize a compact and lightweight power-assisted robot, the size of the artificial rubber muscle should be maintained while increasing the amount of movement. This study aims to develop an artificial rubber muscle that can achieve a wide range of assistance through rope-based force transmission. An artificial rubber muscle is proposed that can transmit force through a human-like pulling motion using a rope. This McKibben-type artificial rubber muscle is enhanced with a power transmission mechanism. The proposed artificial muscle has two layers: an inner layer that is deformed by air pressure to grasp the rope and an outer layer that pulls the rope by contraction. Each layer moves stepwise by supplying compressed air to realize the pulling motion of the rope. In this study, a prototype of the proposed artificial muscle was fabricated, and its operational principle was confirmed experimentally. Additionally, the force transmission performance was verified by comparing the contraction force of the artificial muscle with the tensile force of the rope.

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