This document describes a project to develop a password-based car door lock system using an Arduino Uno microcontroller. The system uses a 4x4 keypad, LCD display, servo motor, buzzer, and other components. It is designed to open the door only when the correct password is entered, and sound the buzzer for an incorrect password. A flowchart shows the process of entering the password, validating it, and controlling the servo motor accordingly. Potential applications are discussed as well as advantages, disadvantages and future scope.

1. PROJECT ON DIGITAL ELECTRONICS AND COMPUTER ORGANIZATION
PROJECT CODE= PR 391
PREPARED BY=
SAJAL MALLICK(123190803079)
RIJU MANDAL(123190803071)
SAHAJADDIN SEIKH(123190803078)
SAGNIK RAY(123190803077)
RAHUL BHATTACHARYA(123190803065)

3.  Introduction
Objectives
 Hardware Requirements
 Circuit Diagram
 Working principle
 Flowchart Diagram of proposed System
Advantages
Disadvantages
Limitations
Applications
Future Scope

4. The aim of our project is to develop “Password Based Car Door Lock
System”.
This is a kind of microcontroller based projects, which created a secure access
for a door which needs a password to open the door.
The system will be used in places where we need more security.
It can also be used in door, car door, lockers, offices, main gate of house, ATM
etc.

5. To develop an intelligent, Whenever the right password will be received, the
controller will accordingly give instruction to servo motor. Servo motor will perform
the action on door unlocking.
The door will close automatically after 5 seconds.
To offer safe and secure, if the password is wrong, then door would remain closed,
denying access to the person.
If give wrong password the buzzer will sound.

6. 4×4 keypad
LCD
Servo Motor
Arduino Uno
MicrocontrollerATmega328
Power Supply
Breadboard
1KΩ, 220Ω Resistor
10KΩ Potentiometer
Buzzer
Connecting wires

7. Microcontroller ATmega 328
Servo Motor
4*4 Keypad
16*2 LCD
Buzzer

8. The ATmega328 is a single-chip microcontroller
created by Atmel in the megaAVR family (later
Microchip Technology acquired Atmel in 2016). It has
a modified Harvard architecture 8-bit RISC
processor core

9. • LCD is a dot matrix liquid display crystal that displays
alphanumeric, Kana(Japanese) characters and symbols.
• Internal refresh is provided.
• All the functions required for dot matrix LCD
drive are internally provided.
Built-in oscillator circuit.

10. A servomotor is a rotary actuator or linear actuator
that allows for precise control of angular or linear
position, velocity and acceleration.[1] It consists of a
suitable motor coupled to a sensor for position
feedback. It also requires a relatively sophisticated
controller, often a dedicated module designed
specifically for use with servomotors.

11. Operates using piezoelectric effect.
• Sound emitter may be extremely low or ear
piercing.
• Driven by low voltages and currents.
• Elements are made from crystals, such as quartz or
Rochelle salts

12. When user give right password then output signal
from microprocessor goes to servo motor and it
rotates anti clockwise and open the door. If
password is wrong then output signal goes from
microprocessor to buzzer and LCD screen and the
buzzer will ring.

14. POWER
SUPPLY
LC
D

15. START
INITIALIZE:
• MICRO-
CONTROLLER
• LCD & KEYPAD
BUZZER
ON
ENTER
PASSWORD
IS
PASSWO
RD
ICORREC
T?
EN
D
EXTRACTI
ON OF
DETAILS
ServoOperat
es Servo
Revers
Ye
s
N
o

16.  Arduino providers are almost available in our country.
 We can control the home appliances by protecting with password from
unwanted hazards.
 We can set password as we wish.
 It is cheaper when compared to other type of automation system.
 It is more effective when compared to other type of automation system.
 It is easy to change to the systems action according to change in situation.

17.  It works only when DC power supply has given.
If you forget the password it is not possible to open the door.
Upon application of brute force, the keypad may get
damaged

18. This simple circuit can be used at residential places and car door to ensure better
safety.
It can be used at organizations to ensure authorized access to highly secured
places.
With a slight modification this Project can be used to control the switching of
loads through password.

19. We can send this data to a remote location using mobile or
internet.
We can add fingerprint sensor so entry will be allowed for the
authorized person using their fingerprints.
We can add fire and LPG sensors so that, the
doors will automatically open.