Doppler Effect: UI Input Method Using Gestures for the Visually Impaired

The project aims to develop a low cost and highly effective motion tracker as an aid for the visually impaired. The basic concept behind the idea is a simple effect popularly known as the Doppler Effect. The project demonstrates the use of very simple, readily available and low-cost electronic components, a microphone, a speaker and a processor. An inaudible sound wave is generated in the air which reflects back after striking any object present in its way. Parameters such as a shift in the frequency, amplitude, and phase shift of the reflected sound wave can be computed by processing the signal that is received by the microphone. Various motions and gestures can be detected and a voice command can be given to the blind person.