A look at some of today’s wearable microcontrollers

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This list is sew awesome!

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Created by Leah Buechley of MIT, and introduced commercially with SparkFun back in 2007, the LilyPad was the first board to feature sew-through contacts for stitching soft circuits. Since then, a number of “ready-to-wear” electronics platforms have emerged, each of which have helped usher in a new generation of textiles that look to redefine wearable technology. In fact, a recent Gartner report revealed that the emergence smart garments will potentially disrupt the market. So much so that embedded clothing shipments are projected to rise from a mere 0.1 million units in 2014 to 26 million units in 2016.

As first noted by MAKE: Magazine’s Boris Kourtoukov, “there’s a plethora of options” when it comes to these microcontrollers. What’s more, they all possess one common trait: they’re powered by Atmel. These so-called body boards are now giving Makers the ability to easily (and affordably) produce their own projects in ways that otherwise would have been unimaginable.

So, without further ado, here’s a look at some of today’s most prominent boards ready for adornment.

The Favorites

LilyPad Arduino

LilyPad is a wearable e-textile technology developed by Leah Buechley and cooperatively brought to life with SparkFun. Each LilyPad was creatively designed to have large connecting pads to allow them to be sewn into clothing. LilyPad can sense information about the environment using inputs like light and temperature sensors and can act on the environment with outputs like LED lights, vibrator motors, and speakers. And yes, they’re even washable.

MCU: ATmega328

FLORA

FLORA is Adafruit’s fully-featured wearable electronics platform. The round, sewable microcontroller weighs in at 4.4 grams and measures only 1.75 inches in diameter. 100% Arduino-compatible, the platform is one of the most beginner-friendly ways to create some amazing wearables. The FLORA family includes an assortment of sensors and RGB LEDs that let you add lighting to your projects, not to mention also boasts built-in USB support, eliminating the need for pesky special cables and extra parts.

MCU: ATmega32U4

GEMMA

Those who are seeking the awesomeness of FLORA but in a tinier package are sure to love another one Adafruit’s wearable platforms: the GEMMA. The board, which packs all of its features in a 1″ diameter package, is programmable with an Arduino IDE over USB. An upcoming Arduino IDE-supported version will feature an on/off switch and microUSB connector.

MCU: ATtiny85

TinyLily Mini

A brainchild of TinyCircuits, the TinyLily Mini is an Arduino-compatible module in an ultra-compact package. Geared towards Makers looking to devise e-textile and wearable applications, the board is very similar to the Arduino LilyPad, with the same processing power and software compatibility – but at 1/12th of the size. The TinyLily Mini also is equipped with sew tabs for eight I/O (four digital, four analog/digital) and four power sew tabs (two for power, two for ground).

MCU: ATmega328

SquareWear

SquareWear is an open-source, wearable board. The Arduino-compatible MCU measures 1.7″x1.7″ in size, and is equipped with a built-in rechargeable Lithium coin battery. It is designed to be sewable, which allows Makers to stich conductive threads through its large pin pads, solder a wire directly onto the pads, or solder snaps onto the pads for quick attachment or detachment from textiles and fabrics. Additionally, the MCU packs an on-board miniUSB port that can be used for programming, charging batteries and serial communication, as well as a color LED, a pushbutton, a buzzer, a light and temperature sensor, and three MOSFETs to drive the high-current load. See, it’s hip to be square!

MCU: ATmega328

Xadow

Seeed Studio’s Xadow is a high-performance, low-power board that is perfectly suited for wearable projects. The microcontroller can be powered either via USB or a Lithium battery. Also, there is charge circuit on this module that you can charge for the Lithium battery through the USB port. Xadow has a diverse selection of compatible modules, including a barometer, UV sensor, LED, OLED and even a full GPS antenna.

MCU: ATmega32U4

Trinket

Trinket goes to show that big things really can come in small packages. In fact, the tiny MCU is one of the lowest-cost Arduino IDE programmable boards on the market today. Adafruit designed a USB bootloader so Makers could easily plug it into any computer and reprogram it over a USB port just like an Arduino. It comes in two different versions: 3V and 5V. Both work the same, but have different operating logic voltages.

MCU: ATtiny85

Pro Trinket

A bigger sibling of the aforementioned board, this 5V unit combines everything you love about Trinket along with the familiarity of the common core found in Arduinos. It’s like an Arduino Pro Mini with more pins along with built-in USB. The Pro Trinket, which still only measures 1.5″ x 0.7″ x 0.2” in size, features 18 GPIO, two extra analog inputs, 28K of flash, as well as 2K of RAM. Like its older brother, the MCU has onboard USB bootloading support and Optiboot support, so Makers can either program their Pro Trinket over USB or with a FTDI cable just like the Pro Mini. (Recently, paying homage to our friends at Hackaday, the Adafruit crew even unveiled a Hackaday.io branded board — black solder mask, Jolly Wrencher and all. And, it’s stunning.)

Atmel MCU: ATmega328

Ones to Watch

BITalino

BITalino is a low-cost, easy-to-use toolkit designed for anyone looking to build self-tracking applications based on information from their body. The platform enables Makers to quickly bring projects entailing body signals and quantified self wearable devices to life, as well as learn how to create actual medical devices — which otherwise can cost upwards of $10,000. BITalino is described by its creators as an out-of-the-box solution that offers an array of Arduino-compatible software and hardware blocks equipped with sensors for electrocardiography (ECG), electromyography (EMG), electrodermal Activity (EDA), accelerometry (ACC), and ambient light (LUX).

MCU: ATmega328

Printoo

Launched by Ynvisible, Printoo is a printed electronics prototyping platform that is capable of bringing everyday objects to life. Comprised of various hardware modules that can all be connected to each other, it is currently the only platform that appears to have a robust flexible form-factor. This enables Makers to quickly and seamlessly create first product concepts for smart wearable devices. Moreover, the board is fully-compatible and programmable with the Arduino IDE.

MCU: ATmega328

SuperDuino

Introduced by Maker Mohsin Farooq, SuperDuino is a coin cell operated, Arduino-compatible board with a built-in 1.7-inch color display and a three-axis accelerometer. As you can imagine, this makes the MCU a suitable match for a wide-range of DIY games, gadgets and most of all, wearable devices.

MCU: ATmega328

Sketching a LilyPad sensor demo mat

The Atmel-based LilyPad Arduino – designed by Leah Buechley and SparkFun Electronics – is targeted specifically at wearables and e-textiles.

The platform, powered by either the ATmega168V (the low-power version of the ATmega168) or the ATmega328V, can be sewn to fabric and similarly mounted power supplies, sensors and actuators with conductive thread.

Recently, a Maker by the name of Duniken created a sensor demo mat for the LilyPad and posted a detailed description of the build on Instructables.

“I wanted a place where I could experiment with the different sensors, but also something that I could use to show examples of what can be done without constantly uploading code,” he explained.

Key project components?

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1 x ProtoSnap – LilyPad Development Board (kit) which includes the following:
• 1 x LilyPad Simple Board
• 1 x LilyPad Button
• 1 x LilyPad Slide Switch
• 5 x LilyPad White LED
• 1 x LilyPad RGB tri-color LED
• 1 x LilyPad Light Sensor
• 1 x LilyPad Temp Sensor
• 1 x LilyPad Buzzer
• 1 x LilyPad Vibe board
• 1 x LilyPad FTDI Basic
• 2 x Conductive Thread Bobbin
• 1 x Needle Set

Duniken also used:

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7 x sewable snaps
• 1 x Piece of fabric big enough to hold all of the sensors
• 1 x Fabric Marking pen

“Although I had the LilyPad Development Board, I decided to use the LilyPad Simple Board so I could use the extra pins as switches,” he clarified.

After drawing up a diagram using LucidChart, Duniken arranged the sensors and switches on the fabric, using the marking pen to indicate where each pin and component would be placed.

“I removed the sensors and used the marking pen to draw the circuit onto the fabric with a ruler to make sure all of my lines were straight. When I had the lines drawn, I again placed the sensors on the mat to make sure that everything lined up the way I wanted it to,” said Duniken.

“I ended up changing the position of the RGB light slightly so the lines were less likely to make contact with the other pins on the LilyPad. I wanted the lines to be part of the final piece so, once I was satisfied with the diagram, I traced the lines with a permanent marker. If I did it over, I would probably color code the lines so that it can be better used to explain how the circuit works.”

Next, Duniken cleaned off the marking pen, stitched on the sensors and other components, sewed the circuits and sketched the code.

“To ensure that the sensors stayed put while I sewed the circuits, I did a quick stitch with plain thread to hold the components in place. Using the conductive thread, I sewed along each of the circuit lines connecting the different components to the LilyPad,” he added.

“Be careful where the Positive lines (red) cross the Ground lines (black). I used a small piece of plastic cut from the LilyPad packaging to make sure that the lines didn’t short. I used hot glue to tack down the plastic so it wouldn’t snag on anything.”

Interested in learning more about designing your own Arduino Lilypad Sensor Demo Mat? You can check out the project’s Instructables page here.

Sew Electric with LilyPad Arduino

The Arduino LillyPad – designed by Leah Buechley and SparkFun Electronics – is powered by an Atmel ATmega168 microcontroller or ATmega328V MCU. The board is primarily targeted at wearables and e-textiles, as it can be easily sewn onto various fabrics.

Buechley, along with Kanjun Qiu and Sonja de Boer, recently published a book about the popular LilyPad titled “Sew Electric.” Featured projects include a sparkling bracelet, a singing monster, a light-up bookmark and a fabric piano. Perhaps most importantly, the book introduces readers to the fundamentals of electronics and programming as well as craft and design practices.

“We want the book to get people excited about electronics and programming. We hope it will help people play, tinker, hack and learn,” Buechley told the official Arduino blog in an interview published earlier this week. 

”There are very few engineering resources that are appealing to young women and girls. We wanted to create an electronics introduction that looks and feels different from anything else that’s out there.”

According to Buechley, the Atmel-powered LilyPad has been used in haute couture fashion, sculpture, dog shows, dance costumes and even fabric robots.

“It’s also been fascinating to research and begin to understand who is using LilyPad. A study I did in 2010 found that while only about 2% of people who build Arduino projects are women, about 65% of LilyPad builders are female. [This is] a spectacular discrepancy,” said Buechley. “I think this shows that the Arduino community can benefit tremendously from tools that connect to different materials, communities and creative traditions.”

The LilyPad creator also noted that wearables and e-textiles offer many admirable qualities, giving new expressive tools to fashion designers, industrial designers and artists.

“They embody appealing juxtapositions–of male and female, soft and hard, new and old,” she explained. “And they’re fantastic vehicles for technological fantasies–bringing to mind the magic cloaks and carpets from fairy tales, the flashy costumes of comic book superheros, and countless sci-fi utopias/dystopias.”

However, Buechley emphasized that companies trying to bring wearables to market are likely to face significant hurdles, at least in the immediate future.

“The timescales of the fashion and electronics worlds are out of sync–though we think of technology as fast moving, clothing styles change much faster, every couple of months,” she concluded. “[Thus far], the most compelling e-textiles work has taken place on smaller scales in the art and design worlds.”

Interested in learning more? You can check out the Atmel-powered Arduino LilyPad here and “Sew Electronics” here.