Tongue Motion Controlled Wheel Chair

The main aim of the Tongue Motion Controlled Wheel Chair project is to provide a Tongue Drive System (TDS) with effective computer access to the people who are suffering from physical disabilities. TDS translates the intentions of user into control commands by finding and classifying their voluntary tongue motion with the help of a small permanent magnet placed on the tongue and an array of magnetic sensors mounted on an orthodontic brace inside or a headset outside the mouth. It is a tongue-operated unobtrusive assistive technology. With the help of an external TDS prototype, we developed a customized interface circuitry and implemented four control strategies to run a Powered Wheel Chair (PWC).

The magnetic sensors are also called as hall-effect sensors. The output voltage of Hall Effect sensor varies in response to the modifications in the magnetic field. We can define sensor as, it operates as an analogue transducer and returns a voltage directly. We can calculate its distance from the Hall plate with the help of a known magnetic field. The control system includes an micro controller and Hall Effect sensor. Micro controller is used to receive the data from the sensor and to drive the motors of the wheel chair in the accurate direction. The micro controller is loaded with a intelligent program which is written by using embedded ‘C’ language. By using the magnet present at different Hall Effect sensors, the micro controller will decide the direction of wheel chair.