Overview / Usage

Objective:

• The objective of this project was to create a more robust, time-saving, safe and better solution to the traditional door locks(the keys and lock maneuver) that have high chances of burglary and therefore put the safety of the residents and goods at risk.
• It reduces the headache of carrying physical keys with you all the time. Losing your keys would not be a headache anymore.
• A smart password system accessible through a phone is better option. However, the smart password locks also come with many disadvantages of cyber attacks, wifi outages, battery problems or the worst case scenario a phone theft. Thus, this project was built on the grounds of basic password lock system with extra features.
• These features include allowing users to change their passwords (only if the user remembers the previous one). This allows users to change their passwords frequently as using only one password for a long time will wear the surface of the buttons.
• This also generates green and red led lights for every correct and incorrect password respectively.
• These lights can be used as an indicator that a person is trying to access the door to the nearby people.
• This project can ultimately be used by both residential and industrial groups.

The user enters the password through the keypad and the number pressed is stored and displayed number is kept hidden for privacy. The stored pin would be compared to the correct pin and see if the pin entered is correct or not and respond by switching the motor on or off. If the pin entered is correct it displays the message "Correct Pin" and opens the door by switching on the motor and again displaying "Door Opened". And if the pin entered is wrong, the message displayed would be "Wrong pin".

Methodology / Approach

Steps for Construction:

Step1: Determining the microcontroller The microcontroller chosen for this project is Atmel 8051 - AT89C51. This application is fairly simple so there is no need for a 16/32 bit microcontroller. These costs low, use low power and the newer variants are more powerful. For a hardware just for checking passwords 8051 family is perfect.

Step2: Determining other components This project uses 6-digits for ensuring high security of the passwords. A L293D is used since the 12V motors cannot be directly used with the microcontroller. A simple LM016L can be used as 16x2 LCD module for displaying messages. Other components like crystals, resistors and a toggle button improve the functionality of the whole system.

Step3: Working

• The code for this project is written in embedded C.
• The default password for the device is taken as "123456" which can be changed by entering a reset code "**00##" which allows users to enter a reset mode, after which they will be prompted to enter the current pin for security reasons.
• If the users fail to do so they will be taken out of the reset mode by default. If they succeed, the users can enter a new custom password.
• After changing the password the user will be prompted with the password screen again where they will have to enter their new custom password.
• For every wrong password, a red led lights glows whereas for every correct password a green light glows.
• Default mode password - "123456", Reset mode - "**00##".

Components Required:

• 1 x AT89C51
• 1 X CAP-ELEC
• 1 X CRYSTAL
• 1 X MOTOR
• 1 X RELAY
• 1 X RESPACK-8
• 1 X BUTTON
• 1 X L293D
• 1 X LM016L
• 1 X KEYPAD-PHONE
• 1 X MINRES10K
• 2 X 33pf CAP

The code for interfacing the hardware required for this project was written in Embedded C where the phone-keypad was interfaced to the microcontroller as the input whereas the LCD and Motor are interfaced as outputs to the microcontroller.

• LM016L- A 16 x 2 LCD display used in this project for displaying messages.
• L293D- A motor driver used to drive the motor in any direction and also control the speed of the motor. We use L293D to connect to the Motor.
• KEYPAD-PHONE- A keypad consisting of numbers and some special characters.
• RESPACK-8- An eight way resistor from common used for interfacing LCD.
• All the other components are used for crystal interfacing with AT89C51.

Technologies Used

This project was created using Proteus software for design automation and Keil as the embedded IDE. This project adds more security and user friendly features to the password based door lock systems available in the market. While also using low-cost components to reduce the overall cost of project, so that it can be accessible to everyone more easily.

Repository

https://github.com/Swati-Verma671/A-six-digit-password-based-door-lock-system-with-improved-security-features