Bluetooth Controlled Door Lock


In this article, we are going to see how to work with Bluetooth, servo motor, and Arduino to create a Bluetooth controlled door lock using the mobile app. Safety and security have become the most important prerequisite for everyone's life;  it is more reassuring if this is under our control. This simple project is one such project which is applicable to everyone.
  1. Arduino UNO
  2. Bluetooth Module
  3. Servo motor (90g)
  4. Connecting wire
  5. Mobile App (BlueControl)
Circuit diagram
HC-05 Bluetooth Module
It has Rx and Tx pins which are connected to Tx and Rx of Arduino.
Servo motor
Servo.write(0) function will make the servomotor spin counter-clockwise at full speed. The Servo.write(90) function will stop the motor and Servo1.write(180) will turn the motor clockwise at full speed.
  1. Open the Arduino Software…


  2. Initialize Serial communication, ”Serial.Available” function is to check the serial whether the serial port is open or not.


  3. If the Serial port is open then the Arduino will receive signals Through HC-05 through pin 0 and 1.

  1. Download the Bluetooth control app from the play store and install it. Turn ON Bluetooth in the mobile>> enter into App>> If  ON, the door lock will be open. Before that,  the function fixes the Arduino and elements near the door such that the Servo motor’s shaft is connected to the Door Lock.

  1. Compile the code and upload the coding to the Arduino.



In this article, we have learned how to create a simple Bluetooth controlled Door lock. This simple project will be very effective for bedridden patients who are facing difficulties in walking. Even small kids with proper guidance can use this for their safety when they are alone at home.