Development of a Tying Tool to Bind a Wire Harness

—Implementation of Tying a Clove Hitch—

Abstract

This paper describes the development of a prototype tool to be used to tie a clove hitch in order to bind a wire harness. The wire harnesses which are installed in airplanes are bound with belt-like strings. The binding process, which involves tying a clove hitch and then a double overhand knot, is still performed by human workers. To promote efficiency, simplifying the process by using tools is more practical than automating it with robots. We propose a tool that has a groove through which a string is pushed to form a clove hitch. The shape of the bottom of the groove is very important in order to ensure that the belt-like string goes through the groove without jamming. We formulated the bottom's shape based on the theory of surfaces and designed the shape to minimize changes in its curvature and torsion. We made a physical model of the prototype tool and confirmed its performance with tying experiments. As a result of the experiments, we found that there was a 93% probability of a successful tie occurring.