SMART DOOR LOCK SYSTEM

Our project is about Smart Door Lock using NodeMCU ESP8266, RFID, temperature and humidity sensor and Blynk application. This system will be focused on rented house to give convenience and ensure the tenants safety. The tenants need to scan their card at the entrance door and the door of their own room will automatically unlocked. Meanwhile the temperature and humidity sensor were used to detect extreme air conditions in the room. Through this, the owner and tenants can know if something unwanted accident such fire happens in the house. 

NodeMCU

RFID RC522, KEY RING, WHITE CARD

Jumper Wire (male to male)

Servo

Breadboard

Temperature and Humidity sensor

LED

This is the wiring diagram of our system

Arduino code - Reading RFID Tag

To connect RFID RC522, first thing we need to do is download a library called MFRC522 which simplifies reading from and writing to RFID tags by visiting the GitHub repo.

To install the file, open the Arduino IDE, choose the Sketch > Include Library > Add .Zip Library

Then select the blynk-library-master and MFRC522-1.4.10

#include <SPI.h>

#include <MFRC522.h>

#define BLYNK_PRINT Serial

#include <ESP8266WiFi.h>

#include <BlynkSimpleEsp8266.h>

#include <DHT.h>

#define SS_PIN 4

#define RST_PIN 5

MFRC522 mfrc522(SS_PIN, RST_PIN);  // Create MFRC522 instance.

char auth[] ="pkVLAYRBbXh7a8Akk1Yr8btIh1nniAHh"; //replace with your Auth code here

const char* ssid = "UniSZA-WiFi"; // replace with Your SSID

const char* password = "unisza2016"; //replace with your wifi Password

#include <Servo.h> 

Servo myServo1; //define servo name

Servo myServo2; //define servo name

#define LED 15 //LED pin

#define DHTPIN 16     // D0

#define DHTTYPE DHT11   // DHT 11

DHT dht(DHTPIN, DHTTYPE);

BlynkTimer temptimer;

SimpleTimer timer;

int fflag = 0; 

int eflag = 0; 

int pos1 = 0;

int pos2 = 0;

WidgetTerminal terminal(V2);

void sendSensor()

{

 float h = dht.readHumidity();

 float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit

 if (isnan(h) || isnan(t)) {

  Serial.println("Failed to read from DHT sensor!");

  return;

 }

 Blynk.virtualWrite(V5, t);

 Blynk.virtualWrite(V6, h);

 Serial.println(t);

  Serial.print("Temperature : ");

  Serial.print(t);

  Serial.print("  Humidity : ");

  Serial.println(h);

}

void setup() 

{

 Serial.begin(115200);  // Initiate a serial communication

   Blynk.begin(auth, ssid, password);

 SPI.begin();   // Initiate SPI bus

  myServo1.attach(2); //servo pin D4

  myServo2.attach(0); //servo pin D3

 myServo1.write(pos1); //servo start position

 myServo2.write(pos2);

 pinMode(LED, OUTPUT);

 dht.begin();

 temptimer.setInterval(2500L, sendSensor);

 mfrc522.PCD_Init();  // Initiate MFRC522

 Serial.println("Put your card to the reader...");

 Serial.println();

 timer.setInterval(1000L, iot_rfid);

}

void loop() 

{

 Blynk.run();

  timer.run(); // Initiates SimpleTimer

  temptimer.run();

}

void iot_rfid(){

 // Look for new cards

 if ( ! mfrc522.PICC_IsNewCardPresent()) 

 {

  return;

 }

 // Select one of the cards

 if ( ! mfrc522.PICC_ReadCardSerial()) 

 {

  return;

 }

 //Show UID on serial monitor

 Serial.print("UID tag :");

 String content= "";

 byte letter;

 for (byte i = 0; i < mfrc522.uid.size; i++) 

 {

   Serial.print(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ");

   Serial.print(mfrc522.uid.uidByte[i], DEC);

   content.concat(String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " "));

   content.concat(String(mfrc522.uid.uidByte[i], DEC));

 }

 Serial.println();

 if( (content.substring(1) == "163 201 73 25") && (fflag == 1))

 {

     Serial.println("User A");

     Blynk.virtualWrite(V2, "USER A" );

digitalWrite(LED, HIGH);

  delay(250);

   digitalWrite(LED, LOW);

     myServo1.write(180);

     delay(8000);

     myServo1.write(0);

    }

     if( (content.substring(1) == "115 232 180 162") && (eflag == 1))

 {

     Serial.println("User B");

     Blynk.virtualWrite(V2, "USER B" );

digitalWrite(LED, HIGH);

  delay(250);

   digitalWrite(LED, LOW);

     myServo2.write(180);

     delay(8000);

     myServo2.write(0);

    }

        else 

    Serial.println("unregistered user");

     digitalWrite(LED, HIGH);

  delay(1500);

   digitalWrite(LED, LOW);

 }

// in Blynk app writes values to the Virtual Pin 3

BLYNK_WRITE(V3)

{

  fflag = param.asInt(); // assigning incoming value from pin V3 to a variable

 // Blynk.virtualWrite(V2, fflag );

}

// in Blynk app writes values to the Virtual Pin 4

BLYNK_WRITE(V4)

{

  eflag = param.asInt(); // assigning incoming value from pin V4 to a variable

}

1. Open the app and create a new project and name it as RFID
2. Click on the select device and NodeMCU. Set the connection type to WIFI
3. Click on the screen and search for tabs to add two tabs with the name Monitoring and Remote.
4. Then click on Remote Access Control Tab. Click on empty space and add two buttons. Click on the first button, set the name as user A and choose virtual pin V3. Next, repeat the same method to create V4 as user B. set both button Mode as Switch.
5. Click on Terminal setting and named it as Terminal and choose V2 as input. Set the New Line to Yes while Input Line and Autoscroll to on.
6. Then click on Gauge setting. Rename the first button as Temp for temperature and choose V5 as Input and set 50 as limit. Then, rename the next button as Humi for humidity and choose V6 as Input and set 100 as limit.

Step 1: connect the LED, RFID and NodeMCU on breadboard

Step 2: For the RFID sensor, the ground pin needs to be connected with ground pin of NodeMCU.

Step 3: The middle pin of temperature and humidity sensor needs to be connected with D0.

Step 4: The anode on LED will be connected on D8 while the cathode will connect to the ground

Step 5: The servo will connect to the NodeMCU and it will act as the lock

This video will show you how the system works