Fibers can be used for articulation, sensing, and actuation in thin robotic parts (<1mm thick).
For example, we used conductive threads to add soft electromechanical switches to a bendable, laser cut polymer sheet using an embroidery machine.
Here is a hinged-plate structure with threads as hinges produced by our aligned embroidery method. The magenta threads are hinges that hold it together, while the white threads heat-shrink to lock in the folded shape. These fibers were installed in pre-cut planar pieces using water-soluble materials to hold the parts in place during sewing.
Aligned embroidery can also install functional fibers into soft materials such as elastomers and textiles. In this tutorial we show how to align an optical fiber along a path in a soft material.