Password Based Door Lock
System Using Arduino
Abhinay Reddy, 13BEC0730, B.Tech ECE, VIT
University
Abstract
Security is a prime concern in our day-today life.
Everyone wants to feel secure. An access control for doors forms a vital part in our security chain. Doors locked using conventional locks are not as safe as they used to be, anyone can break in by breaking these locks. Password based door lock system allows only authorized persons to access restricted areas. The system is fully controlled by Arduino. The password can be entered through a keypad. If the password is matched with the one stored in
Arduino it instructs the motor driver to open the door. The
password can be changed by the user interfacing Arduino with a pc and using a keypad to change the password
Introduction
‘Password based door lock system using Arduino’ is used in places of restricted access. It can be also used to secure lockers and valuable things and confidential information.
Keypad and motor are connected to Arduino. Arduino continuously monitors the keypad and any password entered is compared with the stored password, if matched provides access to the person who entered password, it will not unlock the door if password entered is wrong. The system provides access only to the people who know password. It doesn’t provide access to people who don’t know password
Block Diagram
Arduino
Arduino is a tool for making computers that can sense and control more of the physical world than your desktop
computer. It's an open-source physical computing platform based on a simple microcontroller board, and a development
Arduino can be used to develop interactive objects, taking inputs from a variety of switches or sensors, and controlling a variety of lights, motors, and other physical outputs. Arduino projects can be stand-alone, or they can communicate with software running on your computer (e.g. Flash, Processing, MaxMSP.) The boards can be assembled by hand or purchased preassembled; the open-source IDE can be downloaded for free.
The Arduino programming language is an implementation of Wiring, a similar physical computing platform, which is based on the Processing multimedia programming environment. There are many types of Arduino boards. This project uses a Uno type of Arduino board.
Arduino Uno
Arduino Uno uses an atmega328p microcontroller. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a USB connection, a power jack, a reset button and more. It contains everything needed to support the
microcontroller; simply connect it to a computer with a USB cable or power it with an AC-to-DC adapter or battery to get started.
Keypad
Keypad is used to input the password into the system. It has keys for numeric 1-9. It also has keys to make system accept the
password and to cancel the try if you enter wrong password by mistake. It has 8 output pins.
L293D Motor Driver
This circuit is used to drive the dc motor to rotate when the
entered password is correct. It has a L293D IC, voltage regulator 7805, capacitors, led, resistors. L293D IC has 16 pins of which 4 are output pins. Voltage regulator regulates the voltage entering motor driver. Led is used indicate the power supply to the circuit. It can rotate two motors in either of the directions. IT works on the concept of H-bridge. L293D IC has 2 h-bridges. H-bridge can
DC Motor
This is a motor with low RPM. It can rotate and unlock the door.
Battery Pack
It is a pack of batteries which is used to supply power to the DC Motor.
Scope
Further mobility can be introduced in the circuit using GSM or DTMF modules. When GSM or DTMF modules are introduced in the circuit door can be unlocked using mobile that is linked to the circuit. This way it can be made more secured as only the person with the configured mobile can unlock the door. When someone tries to tamper with the system or door or makes many number of unsuccessful attempts police and owner can be alerted by using Internet of Things technology.
Methodology
Arduino, L293D motor driver, DC motor, keypad and batteries are required to make this circuit. Keypad is connected to the digital pins of Arduino using wires. Output is taken across the digital pins and is given to the motor driver. DC motor is connected to the output pins of L293D. Arduino can be powered by a battery or wall jack or from pc through USB cable. Battery is connected to the power supply pins of motor driver. Power supply for Arduino should not be more than 20V, if it exceeds 20V board will be destroyed. Motor driver should be supplied with power not more than 5V as its voltage regulator cannot regulate voltages above that point. Now the program for the required task is written and loaded onto the Arduino. When power supply to the system is turned on system asks the user to enter the password. After the password is entered Arduino compares the password entered with the stored password, if the passwords match it directs the motor
driver to rotate the motor and unlock the door, if the passwords don’t match it will do nothing
.
Final project diagram
References
Sparkfun.com
Bildr
Arduino playground
