Tongue-Operated Computing

Georgia Tech researchers have developed a new device that will allow users to control computers and other devices, including wheelchairs, with their tongues, an innovation that could help people with paralysis and other disabling conditions.

The Tongue Drive System essentially turns a person’s mouth into a virtual computer, with the tongue filling the function of a mouse, touchpad or joystick.

“This device could revolutionize the field of assistive technologies by helping individuals with severe disabilities, such as those with high-level spinal cord injuries, return to rich, active, independent and productive lives,” Maysam Ghovanloo an assistant professor in the Georgia Tech School of Electrical and Computer Engineering, said in a press release on the university's Web site. Ghovanloo developed the system with graduate student Xueliang Huo.

To operate the Tongue Drive system, potential users only need to be able to move their tongues. Attaching a small magnet, the size of a grain of rice, to an individual’s tongue — by implantation, piercing or tissue adhesive — allows tongue motion to direct the movement of a cursor across a computer screen or a powered wheelchair around a room.

“We chose the tongue to operate the system because unlike hands and feet, which are controlled by the brain through the spinal cord, the tongue is directly connected to the brain by a cranial nerve that generally escapes damage in severe spinal cord injuries or neuromuscular diseases,” said Ghovanloo, who started working on this project about three years ago at North Carolina State University. “Tongue movements are also fast, accurate and do not require much thinking, concentration or effort.”

Movement of the magnetic tracer attached to the tongue is detected by an array of magnetic field sensors mounted on a headset outside the mouth or on an orthodontic brace inside the mouth. The sensor output signals are wirelessly transmitted to a portable computer, which can be carried on the user’s clothing or wheelchair.

The sensor output signals are processed to determine the relative motion of the magnet with respect to the array of sensors in real-time. This information is then used to control the movements of a cursor on the computer screen or to substitute for the joystick function in a powered wheelchair.

The Associated Press reports that early tests involving Georgia Tech students are encouraging, and the team's work has already attracted a $120,000 grant from the National Science Foundation and $150,000 from the Christopher and Dana Reeve Foundation. 

Watch a video of Ghovanloo describing the Tongue Drive system and its applications.