Spotted this project over at the Harnett Lab in the Department of Electrical and Computer Engineering at the University of Louisville:
We continue experimenting with patterning different types of fibers. When fine insulated wire is embroidered onto a piece of linen tape and supplied with a current, it interacts with magnets. Two sets of embroidered coils, one on top and one on the underside of the tape in this video, pull the tape to the left along an alternating magnet array when the coils are energized in a sequence. Flat embroidered coils near magnets are already used as speakers which can be thought of as a kind of actuator. The above tape is an example of a linear motor that is normally built from hard materials, except in a conventional linear motor, the magnetic part moves, and the coils stay still. Below, a single magnet hops along the coil, keeping to the center where the magnetic field is strongest. Here the coil switching rate is increased from 2 Hz in the tape video, to 5 Hz, and the magnet is able to keep up.