This is the second project i did along with my friend saravana.But first to present.Since we had one more weak for the project show. We tried this and we presented it.It is very simple, cheaper and attractive one with wide range of application. we displayed it on the breadboard,because we are not good at soldering and the most beautiful thing in this project is that we got third prize in the intra college competition..
here is that for you....
Our project is to detect the entry of human beings or animals in the restricted areas in banks, museums, hospitals, power plants, etc.
Here, we make use of piezo element to vibration due to the entry of human beings or animals. This piezo will sense the entry of unwanted person or animals and trigger the JFET op-amp and this op-amp will in turn trigger the Timer IC which output is given to the LED and buzzer. So LED glow with the sound to intimate the entry of unwanted persons or animals in the restricted areas.