pressure sensor alarm

PRESSURE SENSOR ALARM

Presented by:Minhaj Fathima (09881A0466)

P.Naveen Kumar (09881A0480)

Contents

Why this? Introduction Block diagram Circuit diagram Operation Applications Conclusion

Why this?

It is very difficult to track the presence of any particular human being in restricted areas. In order to provide security to some protected and restricted areas we have to design a sensor circuit which detects the presence and provides an indication.

Hence the main objective of this project is to design an efficient sensing circuit which provides security.

Introduction

Pressure sensor alarm is a simple circuit to detect any additional pressure falling on an object.

This project mainly operates on basis of piezoelectric effect and operation of IC555 Timer.

In this project a buzzer is used at the output which beeps when additional pressure is detected.

Block Diagram

Piezo

wafer

Mosfet

555 Timer

Piezo Buzze

r

Circuit Diagram

Operation  Working of this circuit is straight forward.

When the circuit is powered by a 9V compact battery, the active piezo-sounder at the output of IC1 starts beeping for a short time and then goes into idle state.

Whenever, the pressure sensor element (Piezo-ceramic wafer) is gently tapped, mosfet T1 is fired by the electric pulse from the sensor through related components and IC1 is again enabled by T1. As a result, the piezo-sounder starts beeping for a short duration.

Electric pulse is generated by piezoelectric effect.

Piezoelectric effect The word “piezo” originates from the

greek word “piezein”, which means “to press”

Discovered in 1880 by Pierre Curie in quartz crystals.

The word piezoelectric means electricity resulting from pressure.

Piezoelectric effect

555 Timer

Waveforms

Applications

Pressure Sensor Alarm can be used as door bell.

It can be used as Carpet Alarm. It can be used as Garage Alarm.

It can be Used as Doormat Sensor.

It can be used at all places where we require a lot of security like in banks, jewellery shops etc.

It can also be used in military for security.

Conclusion This project “PRESSURE SENSOR ALARM” can detect the PRESSURE applied by human

beings. We use a piezo device here to detect them.

We can place these piezo devices inside the floor of

the area, so that it will not be visible to the strangers. And when they (humans) step on the floor tile having a piezo device it will detect the vibrations or we can say it will convert the mechanical energy into electrical energy and the piezo buzzer will get turn on.

This is a low budget project so any one can use

it easily. It can be used at the places where the

interruption of human is not allowed. For example in the bank lockers, jeweller showrooms, high voltage areas and many more. It will help in many ways if we use a high efficiency piezo element and piezo

buzzer.

Thank you...

Any Queries