This wearable input device from MIT’s Media Lab is in the form of a commercialized nail art sticker.
You’ve been there before: Your arms are full and the phone rings. You put everything down only to find out that it was a telemarketer. Or, while in the middle of preparing dinner, you need to scroll down the recipe page on your tablet. With your hands a mess, you first have to wipe them off before proceeding with the instructions. Fortunately, situations like these may be a thing of the past thanks to a new project from MIT Media Lab. Led by Cindy Hsin-Liu Kao, a team of researchers have developed a new wearable device, called NailO, that turns a users thumbnail into a miniature wireless trackpad.
Resembling one of those stick-on nail accessories, NailO works as a shrunken-down trackpad that connects to a mobile device. This enables a wearer to perform various functions on a paired phone or PC through different gestures. And for the fashion-conscious, its creators envision a future with detachable decorative top membranes that are completely customizable to better coordinate with a wearer’s individual style.
Along with its use in hands-full activities like cooking or doing repairs, another potential application for the quarter-sized trackpad includes discreetly sending a quick text message in settings where whipping out a smartphone would be rude. After all, running a finger over a thumbnail is a natural occurrence, so a majority of folks would hardly notice this as a deliberate action to control a gadget.
“Fingernails are an easily accessible location, so they have great potential to serve as an additional input surface for mobile and wearable devices.”
Crammed within the small package of the NailO lie a LiPo battery, a matrix of sensing electrodes, a Bluetooth Low Energy module, a capacitive-sensing controller, and an ATmega328 MCU. With an average power consumption of 4.86 mA, the device can wirelessly transmit data for at least two hours — an ample amount of time for those in a meeting, in class, in a movie theater, or while working around the house.
In order to get started, wearers must first power it up by maintaining finger contact with it for two or three seconds. From there, users can move their index finger up-and-down or left-and-right across its surface, guiding the mouse on its synced device. To select something onscreen, simply press down a finger as if it were a mouse or a touchscreen.
“As the site for a wearable input device, however, the thumbnail has other advantages: It’s a hard surface with no nerve endings, so a device affixed to it wouldn’t impair movement or cause discomfort. And it’s easily accessed by the other fingers — even when the user is holding something in his or her hand,” the team writes.
For their initial prototype, the researchers built their sensors by printing copper electrodes on sheets of flexible polyester, which allowed them to experiment with a range of different electrode layouts. But in future experiments, the team notes that they will be using off-the-shelf sheets of electrodes like those found in some trackpads.
The Media Lab crew has also been in discussion with many Shenzhen-based battery manufacturers and have identified a technology that they think could yield a battery that fits in the space of a thumbnail — yet is only 0.5mm thick. In order to further develop the size of a nail art sticker, the Media Lab worked with flexible PCB factories for a slimmer and bendable prototype, which could conform to the curvature of a fingernail.
We’ll have to go out on a limb and say it: looks like this project ’nailed’ it! Want to learn more? Head over to the project’s official page here, as well as read MIT Technology Review’s latest piece on finger-mounted input devices.
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