After designing award winning wheelchair for quadriplegics, Vaidyanathan started putting the team together to design a technique for application of computers using tongue movements for quadriplegics. They showed that, by inserting a small microphone into the ear, the vibrations from the air pressure changes caused by the tongue can be detected and distinguished for computer commands. These pressure waves, which are basically sound waves, have different wavelengths and amplitudes corresponding to the direction, speed and intensity of the tongue movement. Since the ear canal is so well suited to capture and amplify sound waves, one can measure these waves with a microphone within the ear. For the millions of people living with spinal cord injuries, this hands-free, non-intrusive method to work with computers could enable many people to lead more independent and productive lives.

The researchers have also designed a test and classification system to distinguish the signals of four different tongue movements, which are unique for every individual.
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