Smart backpack for the blind with light sensors, ZigBee, RFID for grid-based selection

This study focuses on the modification of the design of an existing “smart backpack” by integrating photoelectric sensors, Radio-Frequency Identification (RFID) and ZigBee technology in order to assist blind people. The photoelectric sensor emits light continuously until an obstacle blocks its line of sight and receives the reflected light. RFID reader and tags are incorporated to help the user identify specific objects. For indoor position tracking, ZigBee modules are mounted on the ceiling of the target area of application. Moreover, an audio output would be heard to inform the user’s specific distance from the obstacle and the direction where the user was detected, the user’s current location and the identified object. The audio notifications were in the form of text-to-speech generated voice messages stored on an Android application needed to be installed on a smartphone. Bit error rate for ZigBee modules and proximity check for photoelectric sensors and RFID tags were rendered to test each component’s performance as it operates with the overall system. With the aid of the tests performed, proper orientation and inclination of the sensors were found to be significant for more accurate results. The power rating of the system’s battery is also important to ensure that can support all the components for higher efficiency.