Tag Archives: conductive thread

Disney uses store-bought conductive thread to build robot muscles

Researchers have developed an inexpensive way to make artificial muscles using off-the-shelf supplies.

They say Disney World is the most magical place on Earth, but we’d argue that it may come second to their research lab. From 3D-printed plush toys to autonomous sand drawing robots to bipedal droids that walk like animated characters, the Disney Research team continues to dream up some impressive innovations that blend fantasy with the real world.


In an effort to make robotic arm automation more lifelike, a group of Disney engineers have found a way to develop strong, artificial muscles using inexpensive, store-bought conductive sewing thread coiled into a shape that resembles somewhat of a DNA helix.

“Natural muscles exhibit high power-to-weight ratios, inherent compliance and damping, fast actuation and high dynamic ranges. Unfortunately, traditional robotic actuators have been unable to attain similar properties, especially in a slender muscle-like form factor. Recently, super-coiled polymer (SCP) actuators have rejuvenated the promise of an artificial muscle,” the researchers write.

Movement is facilitated through the heating and cooling of the off-the-shelf strings. As the strands fluctuate in temperature, the cables contract and expand like a human muscle, which in turn, pulls the fingers causing the artificial hand to close. While the researchers initially set out to find a low-cost way to create artificial muscles, their project yielded controlled forces in less than 30 milliseconds — actually outperforming the capabilities of a human muscle.


“The average human skeletal muscle has a twitch cycle of over 100 ms, and reaches a steady-state force in hundreds of milliseconds. Furthermore, the peak power- to-weight ratio of mammalian skeletal muscle is 0.32kW/kg, whereas these actuators have been shown to generate up to 5.3kW/kg,” the team adds.

For their demonstration, Disney Research employed a 3D-printed robotic hand — which had been crafted using an AVR powered Makerbot Replicator 2 machine — comprised of four fingers and a thumb with actuators on each tendon enabling a full range of motion. The muscles were strewn along the forearm of the robot to mimic the physical locations of a human arm, while four small computer fans were used to cool the actuators during relaxation. As for its electronics, the arm was driven by an Arduino Nano (ATmega328) along with some simple MOSFET PWM-switching supplies.


“The robot arm was able to perform various grasping maneuvers. The grasps were performed in under a second without the benefit of any feedback sensor, using a lead compensator to improve the speed of finger motions. Each finger can be manipulated individually, and there was no noticeable crosstalk between actuators.”

Does this mean that in the future we’ll see more realistic movements by Disney automations at its parks worldwide? As we wait to find out, you can read its entire paper here.

Music Gloves keep the beat while keeping your hands warm

You know what’s better than gloves? Musical gloves. 

Created by Maker Zhang Zhan, the aptly named Music Gloves were initially designed as a final project for NYU Shanghai’s Interaction Lab. However, this idea certainly has potential, and if somehow given wireless capabilities, can be particularly useful for those walking through campus in colder climates, shoveling during wintry weather, or hitting the ski slopes. Inspired by his passion for both wearable technology and music, Zhan has created a controller right on the tip of his finger that enables user to access both music playback features and emit beats of their own.


How it works is relatively simple: By touching your left thumb with any of the four left hand fingers, you can select one of four musical soundtracks. Meanwhile, by touching your right thumb with any of the other four right hand fingers, you can play one percussion sound as a beat to the background music being played.


Zhan had sewn some conductive thread into his pair of winter gloves, which were connnected to different pins on an Atmel based Arduino board. This way, when two fingers would touch each other, the particular circuit was activated and a certain sound piece would play on Processing. The serial communication between Arduino and Processing is facilitated by the Firmata library.

Watch them in action below!

Video: Enchanted puppets reenact Napoleon Dynamite

Napoleon Dynamite was a 2004 low-budget American comedy that centered around a socially awkward high school student from Preston, Idaho, who lived with his older brother Kip and their grandmother, and navigated through life with his best friend Pedro. Napoleon daydreamed his way through school, doodling ligers (they’re pretty much his favorite animal. It’s like a lion and a tiger mixed… bred for its skills in magic) and fantasy creatures, while reluctantly dealing with the various bullies who torment him.


Well, fans of the flick will certainly enjoy what the team at Bare Conductive recently devised using their ATmega32U4 based Touch Board and some conductive thread. Think 2005 soundboards, only better…

The project reenacts a memorable part of the film, using several audio clips from the scene, which were separated into a dialogue. Each line of the dialogue was connected to a separate electrode on the Touch Board via conductive thread.

Like the film? Then, you’ll love this step-by-step tutorial from the Bare Conductive crew.

Sewn open: Arduino and soft electronics

As several other recent threads on SemiWiki have pointed out, the term “wearables” is a bit amorphous right now. The most recognizable wearable endeavors so far are Google Glass, the smartwatch, and the fitness band, but these are far from the only categories of interest.

There is another area of wearable wonder beginning to get attention: clothing, which has drawn the interest of researchers, makers, and moms alike. The endgame as many see it is smart clothing: the weaving of electronics, sensors, and conventional fabrics into something called e-textiles. However, while athletes, soldiers, and other niches may get sensor-impregnated jerseys sooner, affordable clothing based on exotic advanced fabrics for most consumers may still be 20 or 30 years away by some estimates.

Right now, we have these anything-but-soft computing structures – chips, circuit boards, displays, switches – adaptable for some clothing applications. Still missing are some key elements, most notably power in the form of energy harvesting or smaller and denser batteries. The influence of water-based washing machines and their adverse effect on most electronics also looms large.

How do we cross this gap? It’s not all about advanced R&D; these types of challenges are well suited for experimentation and the imagination of makers. Several Arduino-compatible maker modules – all based on Atmel microcontrollers – have jumped in to the fray, showing how “soft electronics” can help create solutions.

LilyPad embroidery
Maybe I’ve built one or two too many harness assemblies using expensive, mil-spec circular connectors, but the fascinating thing to me is what makes all these boards wearable. Small size is nice, but anybody knows a project needs wiring, right? You’ll notice the large plated holes on the first several offerings: these are eyelets for conductive thread, literally intended to sew these boards to other components like fabric pushbuttons. Many projects also use snaps, similar to 9V battery connections, to disconnect boards for conventional washing of the garment.


The other side of this is the software. One of the attractive features of Arduino is the IDE, real live C-style programming simplified for the masses, with functions designed to perform I/O on the Atmel MCU. Code is edited on a PC or Mac, and compiled into a sketch and uploaded to the board. There are so many examples of code for Arduino maker modules out there available in open source, it makes it easy to find and integrate functions quickly.

If that all sounds crazy, consider the pioneer for this is Leah Buechley of the MIT Media Lab, one of the thought leaders of the maker movement and an expert on e-textiles. She is the brain behind the LilyPad, the original 2” diameter Arduino wearable circa 2007 commercialized through SparkFun, with the most recent version featuring the ATmega32u4 and native USB.

Adafruit took the next steps with two wearable boards.FLORA is slightly smaller than the LilyPad and retains the same familiar circular profile and ATmega32u4 MCU.GEMMA goes even smaller, 1.1” in diameter, packing an ATtiny85 on board with a USB connection for easy development.

Adafruit GEMMA

Not to be outdone by circles, squares and rectangles are still in the mix.SquareWear 2.0 comes in two versions, the 1.7” square variant with a coin cell socket onboard, both including the ATmega328 MCU with simulated USB, high current MOSFET ports, a light sensor, and a temperature sensor. Seeed grabbed the ATmega32u4 and designed it into the Xadow, a tiny 1” x 0.8” expandable unit with integrated flat cable connectors for daisy chaining.

SquareWear 2.0

These aren’t just toys for creating flashing LEDs; there is no shortage of sensors and connectivity, including displays, GPS, Bluetooth, and more compatible with these wearable maker modules. Their popularity is growing: Becky Stern of Adafruit claims there are over 10,000 units of FLORA shipped so far, and they are the darlings of maker faire fashion shows and hackathons.

Besides the upside for makers, maybe this sewing angle will finally allow us to explain electronics to our moms, after all. Until we get to the fulfilled flexible future of e-textiles and more advanced technology, the conductive thread of soft electronics will stitch together creative ideas using somewhat familiar tiny modules with today’s microcontrollers.

This post has been republished with permission from SemiWiki.com, where Don Dingee is a featured blogger. It first appeared there on May 21, 2014.

Adafruit builds a GPS logging dog harness

Adafruit’s Becky Stern has put together a in-depth tutorial that details how to build a GPS logging dog harness using the Atmel-powered (ATmega32u4 MCU) FLORA platform. The project can be completed with conductive thread, so there is no need to break out the soldering gun.

Aside from the Atmel-based FLORA main board, key project components include:

Stern kicks off the GPS logging dog harness by presenting a circuit diagram that displays the following connections:

  • FLORA 3.3V -> GPS 3.3V
  • GPS BAT -> positive coincell battery terminal
  • GPS GND -> negative coincell battery terminal

Next up? Sew the various components, load the logging program in the Arduino IDE or Codebender and upload, paste logs into LOCUS Parser, copy the KML output into a text file and import with Google maps.

It should be noted that Stern has also created a brooch version of the above-mentioned circuit, adapting the design for fashionable humans who want to track and review their trips around town.

Interested in learning more? You can check Becky Stern’s full tutorial on Adafruit’s Learning System here.