An ultrasonic white cane design for visually impaired

In this study, a white cane being the freedom symbol of visually impaired was developed functional with the addition of ultrasonic sensors and electronics devices. Thus, two sensors were placed on the bottom of the cane for avoiding barriers and holes. The knowledge obtained from the sensors has been evaluated in PIC16F877 device, and then a character has been assigned. This character has been sent to a RF receiver module on the receiver circuit from a RF transmitter module. A received character has been compared to the recorded characters in PIC16F877 device, and provided as a hearing message through a headphone-related voice, which was already recorded in the voice record chip. An external amplifier has also been added to the circuit for those situations particularly for hearing problems. In this application, good results have been obtained between 3 centimeters and 3 meters from the designed system.