“Tongue Drive System”: Wheelchairing with the Tongue

The tongue is a versatile organ: It can taste, it is important when speaking and is of good service when kissing. And when it comes down to US-researchers it can do even more. For example, navigate a wheelchair and other electronic equipment.

15.09.2008

It's on the tip of the tongue
© Gary Meek

There are a lot of ideas how to make life easier for severely handicapped people. In the near future they may be able to operate a computer through thoughts. It is already possible to do so through eye movement. Now, researchers at the Georgia Institute of Technology concentrate on a rather flexible muscle of our body in order to enable handicapped people to regain more control over their lives. „We chose the tongue to operate the system because it is directly connected to the brain by a cranial nerve that generally escapes damage in severe spinal cord injuries or neuromuscular diseases - unlike hands and feet which are controlled by the brain through the spinal cord”, explains Dr. Maysam Ghovanloo, project manager for the Tongue Drive System – a system that converts the tongue effectively into a joystick.

It works by fixing a three millimeter wide magnetic strip to the tongue – via implantation, piercing or adhesive. Then, sensors being mounted on an orthodontic brace inside the mouth register the movement of the tongue, somehow similar to playing on a virtual key pad with the tongue. However, in order to navigate electronic devices nearby the output signals from the sensor have to be wirelessly transmitted to a portable computer where software processes the data into real life instructions: to the left, to the right, up and down, one click or double click.

The method has already been tested in a lab: A student cruised with a wheel chair through a room only by moving the tongue. Ghovanloo thinks further and explains that he wants to add dozens of additional user commands:”A 'top left', for example, could mean to switch on the light and a 'downright' turn down the TV.”

Steering the wheelchair with the tongue © Gary Meek

According to the researchers that the system is especially useful because every user can potentially configure a large number of tongue movements depending upon personal preference, body’s anatomy and abilities - each tongue movement representing a different user command. ”Somebody could potentially train our system to recognize touching each tooth as a different command”, says Ghovanloo. That is a significant advantage compared to the common sip and puff devices that acts as a simple switch controlled by sucking or blowing a straw. “A further advantage is the fact that the Tongue Drive System is non-invasive and does not require brain surgery in comparison with related systems”, he explains.

The system still suffers from teething problems, though. The team needs to update the software, downsize the controller, refine the magnet and enhance battery power of the wireless signal transmission. The next step in the further development is to test it with handicapped people at a hospital in Atlanta. Therefore, Ghovanloo’s outlook belongs to the future: “We hope this technology will reduce the need of individuals with severe disabilities to receive continuous assistance from family members or caregivers.”

Kathrin Burghof
REHACARE.de