Wireless control of powered wheelchairs with tongue motion using tongue drive assistive technology

Tongue Drive system (TDS) is a tongue-operated unobtrusive wireless assistive technology, which can potentially provide people with severe disabilities with effective computer access and environment control. It translates users´ intentions into control commands by detecting and classifying their voluntary tongue motion utilizing a small permanent magnet, secured on the tongue, and an array of magnetic sensors mounted on a headset outside the mouth or an orthodontic brace inside. We have developed customized interface circuitry and implemented four control strategies to drive a powered wheelchair (PWC) using an external TDS prototype. The system has been evaluated by five able-bodied human subjects. The results showed that all subjects could easily operate the PWC using their tongue movements, and different control strategies worked better depending on the users´ familiarity with the TDS.