i wnt immediately a ppt on "ultrasonic spectacles and waist belt for visually impaired and blind persons

An electronic navigation system for visually impaired and blind people . This system comprises obstacles around the subject up to 500 cm in the front, left and right directions using a network of ultrasonic sensors. It effectively calculates the distance of the detected object from the subject and prepares the navigation path accordingly avoiding obstacles. It uses speech feedback to know the subject about the detected obstacle and its distance. This proposed system uses AT89S52 based microcontroller based system to process real time data collected using the network of ultrasonic sensors. Based on the address and distance of the detected obstacle, the relevant prerecorded voice message stored in the APR9600 flash memory is invoked. Such voice messages are transmitted to the subject using headphones.