Automatic Anti Theft Alarm and Alert System Using Arduino & GSM Module

About: Working in Bharti Airtel Ltd. as Executive Trainee. My core skill set includes electronic hardware design, telecommunication, optical networks. My objective is to apply my engineering skills to new and excit...

This is basically an intruder alarm or an anti theft alarm. So this project is all about building an anti theft alarm or an intruder alarm using Arduino and PIR sensor. It is possible to enhance this project with many features like adding a GSM module to send SMS alerts to specified mobile numbers when an intruder is detected (when a motion is detected inside the range of PIR sensor).

Objectives of this project:

Detect a motion – an intruder or a burglar using PIR sensorActivate the buzzer alarm upon detection of burglar/intruder – Alarm should sound until Reset switch is pressedSend 2 SMS to a predefined mobile number set inside the program.

Stop the alarm when reset switch is pressed. Also reactivate the SMS alert facility upon reset.

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Step 1: Hardware & Software Requirements:

Hardware :

1. Arduino Uno/Nano

2.PIR Sensor

3.LCD (Optional)

4.Transistor (2N2222)



7.Connecting Wires


Software :

1. Arduino IDE

Step 2: Step 1 : Connections

Connections :
Arduino Pin 7 – Output of PIR Sensor

Arduino Pin 6 – Push button

Arduino Pin 8 – Buzzer Buzzer

Arduino Pin 9 - Tx of GSM (I am using Pin 9 as Rx)

Arduino Pin 10 - Rx of GSM (I am using Pin 10 as Tx)

Connect all the components according to the circuit diagram .

Step 3: Step 2: Program

Find the attached .ino file and burn it on Arduino by using Arduino IDE .Here pin 9 and 10 is used as a Rx and Tx .So for this Software.h Library is required.Else you can use Rx and Tx pin of the arduino.

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    2 Discussions


    Question 5 months ago on Step 3

    I want help in power supply


    Question 9 months ago on Step 3

    can i disable and enable the pir sensor using the gsm?
    so that i wont be sending some false alarms?
    when (home owner is present)
    if so can you send me some codes and diagram on how to do it?
    thank you in advance