Tongue-controlled wheelchair technology

Researchers at Georgia Tech and Shepherd Center release new study
Maysam Ghovanloo with Jason DiSanto

Jason DiSanto of Marietta was paralyzed 4 1/2 years ago after a diving accident in a backyard pool. Not long after he started rehab at the Shepherd Center, he signed up for trials of a tongue-controlled wheelchair system and has been involved in many incarnations since.

“I thought it was something that was neat from a technology standpoint,” says the GE engineer. “It’s actually been quite enjoyable over the last few years. It’s something that I picked up on pretty quickly and was quite impressed with the fast learning time of it.”

The Tongue Drive System (TDS) is controlled by placement of the user’s tongue. It utilizes a magnet—attached to a tongue piercing—and either a headset or a dental retainer. Using sensors in the stud piercing, the user moves his tongue like a joystick to issue commands.

Most people who are paralyzed now rely on sip-and-puff wheelchair control systems. They use a straw to issue four commands (forward, backward, left, right) that move their chair. With TDS, users can operate their phones, work on their computers, play video games, even control their home alarm systems. Basically anything that can be controlled via Bluetooth can be controlled with the system.

Georgia Tech associate professor Maysam Ghovanloo, director of Tech’s Bionics Lab, has headed up the research and coauthored the study appearing in today’s journal Science Translational Medicine.

Ghovanloo started research on the TDS technology in 2005 at North Carolina State University but moved to Georgia Tech specifically to be closer to the Shepherd Center.

With the recent study, testers compared the new system with the older straw technology using them for the very same task. On average, TDS came up three times faster than sip-and-puff while providing the same level of accuracy, says Ghovanloo.

“With sip-and-puff, one of the most important problems is that it’s very slow. With the tongue drive system, all you need to do is touch a particular tooth or landmark in your mouth. It’s much faster.”

The recent study involved eleven people with spinal injuries: seven at the Shepherd Center and four at the Rehabilitation Institute of Chicago.

Study co-author Joy Bruce, PhD, manager of Shepherd’s Spinal Cord Injury Lab said all the participants preferred the TDS.

“They were, of course, disappointed that the technology wasn’t ready for them to be able to use it full time, but were all excited about where the technology was going,” she says. “This is potentially a big deal. The community this serves, they have profound impairments. They have very limited control over their environment, over their devices they interact with. What this device does is allow them more degrees of freedom.”

Although the device doesn’t have FDA approval yet, Ghovanloo estimates that it will take somewhere around two years before it’s available to the public. He created a startup company and is working with Georgia Tech to develop the technology.

Once the device has been tested in the real world, DiSanto said he would be eager to give up his sip-and-puff system and switch.

“I think it could be a game changer. It could interface seamlessly between my computer, my phone, my home, my tablet. I don’t have that capability right now and it would be a huge independence feature. I could do so much more than I’m currently capable of doing myself.

And having to get a tongue piercing for the trial wasn’t an issue, says DiSanto.

“It doesn’t get in the way of me doing business or doing my job. It’s pretty discreet…It’s a little awkward, but I think the advantages far outweigh the inconveniences it creates,” he says. “The slight stigma is diminished by the independence and the capability and the power.”