Development of New Terminal Fixation Method for Synthetic Fiber Ropes

A synthetic fiber rope is potentially capable of replacing a stainless steel wire rope because it is light weight, and has high tensile strength and flexibility. In order to exploit the maximum tensile strength of the rope, a terminal fixation method with a sufficient fixing force is essential. However, this is extremely difficult in the case of synthetic fiber ropes due to their small friction coefficients. This letter proposes a new terminal fixation method combined with a grooved pulley and pin. The grooved pulley is utilized in order to increase the friction between the synthetic fiber rope and the pulley, and the rope is wound around the grooved pulley. The extremity of the rope is fixed at a pin by hanging a loop with a figure-eight knot. The appropriate groove shape is found experimentally and it is confirmed that our method achieves maximum fixation force of 91.3% against the rope breaking force. We provide implementations examples for a long-reach tendon-driven manipulator.

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