Smart Electronic Access Door Lock with RFID & 12V Solenoid Bolt Using Arduino

Educational Notes

This project is designed to be accessible to students from Class 4 to Masters level, with complexity scalable to match different age groups and skill levels.

Learning Objectives:

• Understand basic electronics and circuitry principles
• Learn sensor applications and data collection techniques
• Develop problem-solving skills through hands-on building and troubleshooting
• Apply programming concepts to control hardware and process data
• Connect projects to real-world Nepalese contexts and challenges

Adaptability:

• For younger students (Class 4-8): Focus on assembling pre-built circuits, observing results, and understanding basic concepts
• For intermediate students (Class 9-12): Modify code, experiment with parameters, and explore underlying principles
• For advanced students (Undergraduate/Masters): Optimize designs, add features, conduct research extensions, and analyze performance

Safety Note: Always supervise younger students when working with electricity, heat, or moving parts.

Build a keyless access control system using the HS-S62-L RC522 13.56MHz RFID Reader and 12V DC Solenoid Lock.

Hardware Bill of Materials:

• Microcontroller: Arduino Nano V3.0 Solderless
• RFID Reader: HS-S62-L RC522 NFC RFID Reader Writer Module 13.56MHz
• Solenoid Actuator: 12V DC Solenoid Lock Electromagnetic Electric Control Cabinet Lock
• Driver Transistor: TIP 120 Transistor + 1N4007 Rectifier Diode
• Power Supply: 12v 1.5 Amp Power Adapter

Circuit Pinout & Wiring Connections:

Firmware Source Code (Arduino Uno C++)

#include <Wire.h>
#include <EEPROM.h>
#include <SPI.h>
#include <MFRC522.h>

#define SS_PIN 5
#define RST_PIN 22
MFRC522 rfid(SS_PIN, RST_PIN);

const char* ssid = "GhumtiPasal_WiFi";
const char* pass = "NepalMakers2026";

void setup() {
  Serial.begin(9600);
  SPI.begin();
  rfid.PCD_Init();
  Serial.println("RFID Contactless Reader Ready. Tap Card...");
  
}

void loop() {
  if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial()) {
    delay(50);
    return;
  }

  String cardUID = "";
  for (byte i = 0; i < rfid.uid.size; i++) {
    cardUID += String(rfid.uid.uidByte[i] < 0x10 ? "0" : "");
    cardUID += String(rfid.uid.uidByte[i], HEX);
  }
  cardUID.toUpperCase();

  Serial.println("Scanned Card UID: " + cardUID);
  Serial.println("Access Granted! Syncing record with database...");
  rfid.PICC_HaltA();
  rfid.PCD_StopCrypto1();
  delay(2000);
}