Electronic Watch Dog Project

Download Project Document/Synopsis

Traditionally and even now many people have pet dogs stationed at their entrance. The purpose of the dogs is that they bark whenever a person enters through the door. This is what names this project as Electronic Watch Dog Project as it performs the same task of detecting the presence of a person at the entrance of a premises.
A pair of IR sensor transmitter and receiver are placed at the entrance of the premises that needs to be secured. This is what does the trick in our case in this project. When a person or an intruder who doesn’t knows about the security device installed at the entrance enters through the door, the IR rays gets cut. This cutting of IR rays triggers a series of events in the circuit eventually ringing a burglar alarm. Hearing the alarm the owner of the premises can come to know that someone has entered through the door. Similarly, this device can be installed whichever perimeter is needed to be secure from intruders.
The IR rays from transmitter reaches the IR receiver making it signal to the 555 IC know that currently there is no present in between the sensors. But as soon as an intruder cuts the IR rays, the receiver output changes resulting the 555 IC to trigger. This eventually leads in triggering UM66 IC. Due to these series of events the speaker connected at the output of the circuit board starts ringing thus notifying about the intruder at the secured permeter.