[Mikst] has been working on wearable electronics and sensors for a long time, and shared the results of a different kind of bend sensor that fits directly onto the skin. It’s true that this kind of sensor design isn’t re-usable, but it is also very simple and inexpensive. It’s just a proof of concept right now, but we could see it or some of the other ideas [Mikst] tries, used in niche wearable applications where space is critical, like cosplay.
At its heart the sensor is made from two strands of conductive thread and a small strip of stretchy, conductive fabric common in wearable e-textiles. It is stuck directly to the skin using a transparent, non-woven medical adhesive dressing that is particularly good at conforming to contoured areas of the body. In this case, it is used to stick the stretchy piece of conductive fabric directly onto [Mikst]’s knuckle, where it responds to even small movements. You can watch a multimeter measuring the resistance changes in the video, embedded below.
We’ve seen [Mikst]’s work before in finding unusual solutions to e-textile problems, such as a three-conductor pivoting connection used to mount a wearable hall effect sensor.
Continue reading “Skin-Mounted Wearable Bend Sensor Gets Close And Personal”
Fabrics with electrical functionality have been around for several years, but are very rarely used in mainstream clothing. The fabrics are very expensive and the supply can be unreliable. Frustrated by this, [Counter Chemists] developed PolySense, simple open-source technology to make any fibrous material into a conductive material that can be used to sense pressure, stretch, capacitive touch, humidity, or temperature.
PolySense uses a process called in-situ polymerization, effectively dying a fabric to become piezoelectric. This is done by first soaking the fabric in a mixture of water and the organic compound pyrrole, and then adding iron chloride to trigger a reaction. The polymerization process that takes place wraps the individual fibers of the fabric in conductive polymer chains.
Instead of just uniformly coating a fabric, various masking techniques can be used to dye patterns onto the fabric for various use cases. The video after the break shows a range of these applications, including using polymerized gloves and leggings for motion capture, a zipper that acts like a linear potentiometer, and touch-sensitive fabric. The project page lists sources for the required chemicals in both Europe and the US, and we look forward to seeing what other applications the community can come up with.
The project is very well documented, with a number of scientific papers covering all the details. [Counter Chemists] will also be presenting PolySense at the 2020 Virtual Maker Faire.
This technology can also be used to make a fabric piano with a lot less effort. On the more mechanical side of things, you can also 3D print on pre-stretched fabric to make it pop into 3D shapes.
Continue reading “Dyeing Fabric To Create Sensors”
Wearables are kind of a perplexing frontier for electronics. On the one hand, it’s the best possible platform for showing off a circuit everywhere you go. On the other hand, the whole endeavor is fiddly because the human body has no straight lines and moves around quite a bit. Circuits need to be flexible and comfortable. In other words, a wearable has to be bearable.
[Konstantin], [Raimund], and [Jürgen] have developed an intriguing system for prototyping e-textiles that opens up the wearables world to those who don’t sew and makes the prototyping process way easier for everyone.
It’s a small and portable roll-on ironing device that lays down different kinds of custom ‘tapes’ on to textiles. The conductive fabric tapes can be used as touchable traces, and can support components such as flexible e-ink screens and solar panels. Some tapes provide single or multiple points of connectivity, and others are helper substrates like polyimide tape that multiply the possibilities for complex circuits.
The device uses a modified soldering iron to transfer the tapes, which are loaded onto 3D-printed spools that double as the wheels. Check it out after the break — there’s a 30-second tour and a 5-minute exploration of the whole process.
Everyone needs to prototype, even the seasoned stitchers. The next time you’re thinking in thread, throw some magnets into the process.
Continue reading “Rapid Prototyping System Gives Wheels To Wearables”
Finding a killer application for e-textiles is the realm of the hacker and within that realm, anything goes. Whether it’s protecting your digital privacy with signal shielding, generating audio with a wearable BeagleBone or 555 timer, or making your favorite garment into an antenna, the eTextile Spring Break is testing out ways to combine electronics and fabric.
You may be asking yourself “What are e-textiles good for?”. Well, that’s an excellent question and likely the most common one facing the industry today. I’m afraid I won’t be able to give a definitive answer. As an e-textile practitioner, I too am constantly posing this question to myself. There’s an inherently personal nature to fabric worn on the body and to our electronic devices that makes this answer elusive. Instead of trying to fabricate some narrow definition, what I offer is a look at topics of interest, material experimentation, and technical exploration through the lens of a week-long event held recently in New York called eTextile Spring Break.
Continue reading “ETextile Spring Break Tackles Signal Blocking, Audio Generation, And Radio Transmissions”
California textiles artist and musician [push_reset] challenged herself to make a wearable, gesture-based synth without using flex-sensing resistors. In the end, she designed almost every bit of it from the ground up using conductive fabric, resistive paint, and 3-D printed parts.
A couple of fingers do double duty in this glove. Each of the four fingertips have a sensor made from polyurethane, conductive paint, and conductive fabric that is connected to wires using small rivets. These sensors trigger different samples on an Edison that are generated with Timbre.js. The index and middle fingers also have knuckle actuators made from 3-D printed pin-and-slot mechanisms that turn trimmer pots. Bending one knuckle changes the delay timing while the other manipulates a triangle wave.
On the back of the glove are two sensors made from conductive fabric. Touching one up and down the length will alter the reverb. Sliding up and down the other alters the frequency of a sine wave. [push_reset] has kindly provided everything necessary to re-create this build from the glove pattern to the STL files for the knuckle actuators. Check out a short demonstration of the glove after the break. If you love a parade, here’s a wearable synth that emulates a marching band.
Continue reading “Second Skin Synth Fits Like A Glove”
Looking for a fun wearable electronics project? While you can buy specific fabric and conductive thread for your projects, sometimes you can even find conductive fabric where you might not expect it!
In this latest video by Adafruit, [Becky Stern] goes undercover at a fabrics store with her trusty multimeter to find some new material that can be used for electronics projects! While pickings are slim, she made some useful discoveries — most metallic fabrics aren’t conductive, but some are — You’ll definitely need to take your multimeter with you.
Another funny quirk is that some fabrics are only conductive in one direction! Which could make for a really cool project that seemingly defies conventional wiring — or you can sew a conductive thread perpendicular to the continuity to connect it all together.
Continue reading “Poking Around Textiles With Your Multimeter”
If you want to capture a 3D model of a physical object, you could use a Kinect, a couple of lasers, constructive light, or even a simple touch sensor mounted on a robotic arm. Those are all expensive devices, and somewhat unnecessary now that you can just throw a blanket over an object and get a 3D model instantaneously.
The project is called IM BLANKY and it’s supposed to reproduce 3D shapes by simply throwing it over an object. The petals in the flower motif are pieces of conductive fabric that serve as contacts for the electrified tassel in the center of each flower. When the blanket is thrown over an object, the tassel is pulled by gravity, makes contact with one of the six conductive petals and sends a tilt switch to a microcontroller.
While we’re not too sure about the resolution IM BLANKY will provide with only 20 tilt sensors, but we imagine this could be used for a few medical applications.