4.Keypad-Controlled Lock System with Servo and I2C LCD Using Arduino

 Keypad-Controlled Lock System with Servo and I2C LCD Using Arduino

Components Needed:

1. Arduino board
2. 4x4 or 4x3 Keypad
3. I2C LCD
4. Servo motor
5. Jumper wires
6. Breadboard (optional)

Connections:

1. Keypad: Connect the keypad pins to Arduino digital pins (e.g., rows to pins 9, 8, 7, 6 and columns to pins 5, 4, 3, 2).
2. I2C LCD: Connect the SDA and SCL pins to Arduino I2C pins (A4 and A5 on an Uno).
3. Servo: Connect the servo motor's signal pin to pin 10.

Example Code:

#include <Keypad.h>

#include <Servo.h>

#include <Wire.h>

#include <Adafruit_LiquidCrystal.h>

const byte ROWS = 4; // Number of rows

const byte COLS = 4; // Number of columns

char keys[ROWS][COLS] = {

  {'1', '2', '3', 'A'},

  {'4', '5', '6', 'B'},

  {'7', '8', '9', 'C'},

  {'*', '0', '#', 'D'}

};

byte rowPins[ROWS] = {9, 8, 7, 6};    // Connect to row pins of keypad

byte colPins[COLS] = {5, 4, 3, 2};     // Connect to column pins of keypad

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

Servo myServo; // Create a Servo object

Adafruit_LiquidCrystal lcd(0); // Create LCD object

int servoPin = 10; // Servo motor connected to pin 10

String inputPassword = "";

const String openPassword = "9870";

const String closePassword = "2413";

void setup() {

  myServo.attach(servoPin); // Attach the servo to the pin

  myServo.write(0);         // Set initial servo position to 0 degrees

  lcd.begin(16, 2);         // Initialize the LCD with 16 columns and 2 rows

  lcd.print("Enter Password:");

}

void loop() {

  char key = keypad.getKey();

  if (key) {

    if (key == 'D') {

      // Check password when 'D' is pressed

      if (inputPassword == openPassword) {

        lcd.clear();

        lcd.print("Lock open");

        myServo.write(90); // Move servo to 90 degrees

      } else if (inputPassword == closePassword) {

        lcd.clear();

        lcd.print("Locked");

        myServo.write(0); // Move servo to 0 degrees

      } else {

        lcd.clear();

        lcd.print("Wrong Password");

      }

      delay(2000); // Display message for 2 seconds

      lcd.clear();

      lcd.print("Enter Password:");

      inputPassword = ""; // Clear input

    } else if (key == '*') {

      // Clear input when '*' is pressed

      inputPassword = "";

      lcd.clear();

      lcd.print("Enter Password:");

    } else {

      // Append the key to the inputPassword

      inputPassword += key;

      lcd.setCursor(0, 1); // Move cursor to the second row

      lcd.print(inputPassword);

    }

  }

}