Paralysed after a diving accident in 2009, Jason DiSanto controls a wheelchair with his tongue.
(Screenshot by Michelle Starr/CNET Australia)
A magnetic tongue stud is used in concert with a headset to allow the wearer to steer a wheelchair just by moving their tongue inside their mouth.
A team of researchers at Georgia Tech has created a method of wheelchair steering that is much faster (and potentially more accurate) than the "sip-and-puff" (SNP) method of controlling motorised wheelchairs. Rather than blowing or sucking air through a tube, all the user has to do is move their tongue around their mouth — opening up a new avenue of mobility for paralysed people.
Led by associate professor in the School of Electrical and Computer Engineering Maysam Ghovanloo, the team has spent more than five years developing the technology. It utilises a magnetic tongue stud and a headset that senses the changes in the magnetic field as the user moves their tongue in their mouth.
This information is then sent wirelessly to a connected smartphone, which tells the wheelchair where to go. Different regions of the mouth are calibrated by the user for moving left, right, forwards, backwards and stopping completely.
The system was tested on an able-bodied group and a group of 11 people with tetraplegia. On average, the tetraplegic group was able to manoeuvre the motorised wheelchair three times more quickly than using SNP, with about the same level of accuracy — even though over half the patients had years of daily experience with SNP.
"That was a very exciting finding," said Ghovanloo. "It attests to how quickly and accurately you can move your tongue."
The tetraplegic group was tested over six weeks, with one session a week — but even within the first two sessions, the researchers noticed a marked improvement. "We saw a huge, very significant improvement in their performance from session one to session two," Ghovanloo said. "That's an indicator of how quickly people learn this."
The next step for the researchers is to take the Tongue Drive System out of a controlled clinical environment and test it in real-life situations.
The results of the research, "The Tongue Enables Computer and Wheelchair Control for People with Spinal Cord Injury," can be found online in the journal Science Translational Medicine.