Coiled polymer actuators have become increasingly popular since their introduction in 2014 by the Baughman group, but most tutorials show how to produce short segments. To produce a fiber that could work with the sewing and embroidery equipment in this tutorial, we used a slip clutch from Dynatect (part PAO16-4-4) to dispense the fishing line under controlled tension from a spool that was rotated to twist the fiber onto a take-up spool so that continuous lengths (1m and greater) were produced. These coils, made from 8-lb nylon fishing line, have an approximately 1mm diameter and can be run through the sewing machine couching foot.
The slip clutch prevents the black spool at the right from spinning freely around its axis, applying enough tension to keep the coiling conditions at a steady state. The location of the coiling front is controlled by the speed of the take-up motor (left) and the speed of the coiling motor (right). The image below shows coiled fibers attached to a stretchable fabric by the sewing machine couching foot with a three-segmented zig zag stitch.
