The main objective of this project is to provide safety for blind people from obstacles. This device ensures safety for the blind while walking. The device is to be carried by blind and when the device senses any obstacle it gives the message through voice processor and accordingly he can move. The entire design is built on the concept of embedded system and AT89C52 microcontroller is used which monitors the components.
Circuit design and working:
AT89C52 microcontroller is the heart of the design. The IR waves are transmitted into free space and when these touch the obstacle its gets reflected. The reflected waves are receives by the IR receiver. The demodulator is used to process the signal and it gives the processed signal to the microcontroller. The microcontroller then drives the relay connected to the dsp voice processor by which the blind person can come to know about the obstacle. The microcontroller is provided with an oscillator frequency of 12mhz, and a reset logic signal is fed to the microcontroller so restart when bugs occur. The entire circuit is provide with an rechargeable battery source. The advantage of selecting AT89C52 microcontroller is that it has an 8kb of flash memory. The relay is to drive the dsp voice processor according to the given signal.
The device is very helpful for the blind people to go in a exact path without the help of others. Instead of using IR signals we can also use light signals detecting obstacles. The IR signal response for after the detection of obstacle is delayed by 0.2 seconds which is to be overcome.
Download Electronic Safety Assistance for Blind Using Micro controller and Dsp Voice Processor.