We used a GoPro to capture each step in the process of weaving a smart textile and compiled roughly 6 weeks of work into this video. We show the two tapestries that emerged from this weave, one that didn’t work so well and the other that did (see force fabric post below). in both cases, we were attempting to weave structures that could be used to sense force and tigger color changes in response.
This is a first prototype of a vision of a force-fabric. When integrated into a garment, this textile could capture and replay how your body made contact with other bodies in the world. Those bodies may be human, created through the experiences of hugs or holding children, but they may also be of nonhuman forces – heavy winds or couches pressed upon ones back. The concept is to think of ways technology can make us aware of how we are physically supporting and supported by other objects and environmental forces. It sees garments as a interesting surfaces of intersection between self and other.
We created this first textile by double weaving sections of color changing yarn (resistive heating wire painted with a mixture of thermochromic pigments that change at different temperatures) on the front face and then integrating conductive pads on the back or under layer of the fabric. We used a tapestry technique to integrate a second piece of conductive yarn along a segment of the warp above the touchpad such that when it is pressed it completes the circuit. The double weaving structure makes the connective “guts” invisible from the front. Thus, the textile does not invite you to touch and poke it (how would you know where to touch), it simply captures a “picture” of the different press regions.
For those interested in recreating something like this, here are some information to work from. This draft shows the general structure of each touch pad, which leverages the structure of double weave to hide the conductive pads on the back of the fabric and highlight the thermochromic on the top.
This was woven on a Schacht 8-Shaft Baby Wolf, warped with 10/2 pearl cotton in natural color at 20 ends per inch.
I hand dyed sections of the warp to achieve something ikat-like, largely taking inspiration from documentation of a warp painting class at my local weaving shop. The colors turned out so much darker and astro-pop looking than I was hoping but, luckily, when I mixed them into the warp, they mellowed out. The idea was to make the overall feel of the fabric less square and more painterly. I chose the colors to complement the transition states of the thermochromic yarns.
We used the conductive yarn we had on hand for the sensing (and sadly, we don’t know where it came from) but it appears to be entirely made of stainless steel fibers which have been spun. The fibers like to “grab” the other yarns and they feel really nasty in the hand. I did one experiment adding them along the warp, which was a disaster as they grabbed the other yarns creating massive knots during warping and then broke frequently. On the plus side, they are easy to repair by just trying them back together.
We experimented with several methods for creating the color changing yarns. Playing around with combinations that could couple the painted fiber with a heating element. In some cases, we hand-spun the fibers together (shown in the figure below) with a conductive wire (38, 40AWG magnet wire) but that was finicky and prone to breaking.
We had the best results hand painting a cotton covered copper yarn we sourced from wires.co.uk. The thinner the wire, the better the heating. What seems to make this yarn work so well is that the copper inside the cotton covering is uninsulated, so lots of heat travels between the wire and cotton. It also makes for much more pleasant soldering and attaching.
Thermochromic Paint Mixture
We created our final paint mixture by mixing:
3 parts blue thermochromic that activates at 28°C;
1 part red thermochromic that activates at 43°C;
4 parts liquitex clear acryllic gel medium.
We cut lengths of our wire/yarn and then painted by hand. This makes it a little gloopy and uneven, but it works. The transition from purple to red to blue was the most notable in our experiments. The image below shows two different transitions between purple, blue or red, and white. You can see how the pink/red transition is much more visible.
The general structure of the weave puts the thermochromic sections on the top of the fabric while hiding the conductive yarns behind the fabric. The design follows the schematic outlined below:
The general rule of thumb was that one needed two rows of cotton yarn in between a conductive yarn to prevent unintended crossing. Here is a structural view of the yarn paths and draft of the top layer yarn for a SINGLE section of color change:
You can see the black yarn is the cotton, the purple is the thermochromic, and the teal is a second segment of cotton. The thermochromic leads are routed through the “middle” or between the two layers until their are integrated into the visible surface of the yarn.
Here is a draft and yarn paths for the BOTTOM layer that has the press pads. The green is our conductive yarn, the grey is the cotton yarn, and the red is a funny little yarn we call a “warp insertion.” basically, it is a yarn we route through the bottom of the weave to reach the center point of the press pad and then manually pull through the warp using a crochet hook. This adds the yarn to the surface while making it very hidden.
We are in the process of making a PCB that can interface with the entire textile, in the meantime, we have added PCBs to control a single spot or 3 spots on our lab GitHub page. Thank you Chad Di Lauro. More files should be there as we continue development. Right now, they are powered by the wall, using 12V 5A power supplies and are controlled via Arduino Pro Mini.
Here is a tie up for the pattern. The frame threading is correct but I did lots of improvising on the treadles, so that is not correct for the drafts you see above. I also had to do lots of manipulations by hand.I made this in Excel, which can BARELY handle all of the information. Again, click to make larger.
We have created our own smart textiles design software, AdaCAD, that helps immensely with drafting smart textiles. We expect to release this on GitHub once we have it fully integrated and talking to our TC2 loom. It will be released with a GPL license and we would like the community to get involved in development.
With the TC2 loom, we hope to recreate this general structure to create a wearable garment with custom placed sensing and actuating regions. Stay turned.
This work was supported by lots of folks including: Chad Di Lauro, Clement Zheng, Shanel Wu, Mikhaila Friske, Gaspard Bos, and the Schacht Spindle Company.
This is a summary of my (Gaspard Bos’) work done at the Unstable Design Lab in the month of July 2018 as a practice-based researcher and residence. I sought to do a project abroad in an inspiring space, with inspiring people, where I could work with interactive, connected and intelligent tech on social/societal issues that are my drive as a designer. I was happy to have been given the opportunity to work with smart textiles on the topic of parenthood at the lab and build on the research and work that has already been done there.
The project I developed is called Pathfinders: Felt Experience versus Embodied Statistics. Pathfinders invites participants to experience and play with anxieties that our present day risk society projects upon prospective parents. Conceptualized as a designerly form of autobiographical storytelling, the experience is intended to prompt reflection and conversation on gender stereotypes, societal expectations that are reflected within and reinforced by statistics on health and parenthood. The piece is part of a broader collection of design objects and technologies that tell personal stories about the felt experience of becoming parents in a world of increasingly sophisticated techniques for quantifying risk, intervention, and genetic modification. The work was completed in collaboration with the Unstable Design Lab and used the groups experience in designing smart wearable technologies to produce an experience that is not only about becoming parents, but brings the participant into an embodied and felt experience of navigating the choices facing prospective parents.
String Figuring is a project that wanders: starting from a motivation to explore fiber-arts for feminist retaliation and culminating in the design and development of a novel soft sensor. Perhaps best characterized as an act of reflective design or critical making, the story of design that we will tell in this paper, which will be presented at CHI 2018’s Late Breaking Work session, ties together feminist theory, material studies, and cultural reflection to suggest a novel form of sensing – a string figure sensor.
The string figure sensor is a concept or early prototype for a string-based sensor that can know something of its own shape. We created a proof of concept by knitting conductive thread and wool around a wire core, resulting in a semi-rigid loop that feels similar to a pipe cleaner in one’s hands. When someone plays with the loop, the crosses and knots created in it result in measurable changes in resistance. We take resistance measurements at five points along the length of the loop to create a resistance “signature” that correlates to various shapes or figures created with the string.
Collaborative survival is a term coined by anthropologist Anna Tsing to describe how our (human) ability to persist as a species is deeply entangled with and dependent upon the health of a multitude of other species. We (Jen Liu, Daragh Byrne, and Laura Devendorf) wrote a paper that explores how this term inspires design. Specifically, Jen Liu reflects on collaborative survival within the context of designing tools for mushroom foraging. Photo Credit: Jen Liu. More Information: fieldcomputing.org
Emilia Louisa Pucci, and independent artist and designer, worked in the lab this summer exploring textile-based display. We created this circular weave using wool dyed with thermochromic pigments and embroidered heating wire. When current is supplied to the heating wire, the wire heats up and the yarns next to the wire change colors. We arranged the heating wire into several distinct spirals that become visible the longer the viewer is present. What was most interesting about this display is the slowness and the idea that the display will likely never repeat the same pattern. The heat created by the yarns varies based on environmental factors and creates a slightly different abstract pattern each use.
Another interesting discovery from this project is that, since wool is a great insulator, the heating wire running along the backside of the fabric is not visible on the surface. This allowed us to create an animation on the surface of the fabric and a different “negative space” animation that was only visible on the back side of the fabric.
Emilia presented the piece at Intersections, a conference on collaborations in textile design research in the UK. She equipped the final installation with a proximity sensor that would trigger the animation upon the viewers approach. The installation runs off an Arduino, motor driver (to give the heating yarns the current they require), and 12V power supply.
Published at Designing Interactive Systems (DIS) 2017. This paper describes how the metaphor of the hybrid shapes how we imagine the future of technology. Drawing on feminist technoscience, We propose the alternative metaphor of coproductions to provoke visions for human-technology futures.