Forearm Gestures Remotely Control Computers and Drones

I expected “gesture control” to be immediately intuitive. But as I slip on the MYO—a flexible band that fits around my forearm—a cursor on a laptop in front of me begins somersaulting wildly across the screen, tracking my erratic arm movements. I focus, slow down and try to get a feel for this new tool.

“Move your wrist right—and now left,” instructs Stephen Lake, co-founder of Thalmic Labs of Waterloo, Ontario, the start-up behind the MYO (named after a biological prefix denoting muscle). As I do, the engineering interface on Lake’s computer screen registers a burst of raw data—peaks and dips of scrolling electrical activity produced by my engaged skeletal muscles. Then, the program flashes the words “right” and “left,” confirming that it understood my actions. I’m beginning to get the hang of this.

I’m in a New York City office, where Lake is offering the first hands-on demonstration of the MYO, a new gesture control interface. The armband has insulated electrodes that detect small volts of electricity that muscles produce when they expand, contract or move in any direction. The band transmits those data wirelessly to software, which translates them into commands for a computer, drone or other electronic device. The idea is to control these devices hands-free, and without the need for cameras that would track my motions.

The MYO prototype resembles a clunky bracelet of the type Wilma Flintstone might wear. The final product—the first batch ships out at the end of the year—will resemble a sweatband, Lake says. The prototype is fashioned out of 3-D–printed black plastic, embedded with several muscle activity sensors. They act as electromyographs, or instruments that detect minute electrical signals on the order of microvolts, produced by activated muscles. “The challenge is picking up those tiny muscle activity signals and ignoring all the noise,” Lake says.

An inertial sensor, embedded in one of the MYO’s segments, registers motion made with the arm, such as a rolling wave or a back-and-forth swing. Using a large set of data, Lake and his co-founders applied machine learning to train the MYO to recognize specific signals while canceling out background noise. “What I am impressed with about the MYO is the combination of state-of-the-art pattern recognition and machine learning algorithms to detect gestures, with a strong base of acquiring data,” says Daniel Stashuk, an electrical engineer at the University of Waterloo who has no financial ties to Thalmic Labs, in a phone interview. “Marrying those two things together is quite useful.”

So far, the sensors can recognize around 20 gestures, from a sweeping arm to a clenching fist. On the finest end of the spectrum, the MYO responds to a thumb and finger pinching together. “It’s not that we couldn’t detect smaller motions, but if we did, there would be so many false positives,” Lake explains.

The MYO’s greatest limitation, Lake thinks, is the fact that the user must wear it. If the armband is not wrapped around the forearm, it cannot detect movement. Current challenges to improving the MYO’s performance, he adds, include better defining an intuitive set of gestures that could be applied across a wide variety of applications. The team is also working to refine the MYO’s algorithms to improve balance between sensitivity and false gesture detection.

Moving on with the demo, Lake opens up a computer game called Counter-Strike, swooshing his arm up and down, left or right in order to change perspective in the virtual world as well as flexing his thumb to the top of his palm to shoot a gun. Lake says the MYO has broader application than gaming, however. Although Lake has received inquiries from companies specializing in gaming, music, toys, drones and more, he has also been in touch with labs that are engaged in biosignal and electromyography analysis, and some that work in prosthetics. He thinks the MYO could find a place in serious games used to help rehabilitate people who have suffered a loss of motor control by providing patients with feedback as they progress in relearning certain movements.

The MYO could also assist partially paralyzed or impaired persons, so long as they have a functioning forearm. “If they can complete gestures or some set of gestures, then yes, this can be used to control their environment,” Stashuk says. That could allow impaired individuals to control light switches, turn on a television and command electronic beds or wheelchairs.

In the office, after a bit of practice, I begin to get a grip on gesture control, directing the cursor to hover over objects on Lake’s screen or turning right or left in Counter-Strike’s dark halls. Although I still can’t manage to get the virtual gun to fire, if Thalmic realizes its vision, I’ll have plenty of opportunity to practice in the future.

“As we move away from desktop computing, we’re really interested in this idea of mobile, always available, wearable computing,” Lake says.

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