How to Build a Smart Toll Tax System Using Arduino Uno

The Smart Toll Tax System uses an Arduino Uno as the central controller to automate a vehicle access barrier. When a vehicle approaches, the driver presents an RFID card or tag to the RC522 RFID reader. The reader uses radio frequency identification to scan the unique identification number stored on the tag and sends this data to the Arduino Uno using the SPI communication protocol. Once the Arduino receives the ID, it processes the code to verify authorization. If a valid card is scanned, the Arduino signals the servo motor to rotate, lifting the barrier gate to let the vehicle pass. Simultaneously, the Arduino updates the 16x2 I2C LCD display to show a confirmation message like 'Access Granted' and triggers a buzzer to provide an audible beep confirming the successful transaction. After a short delay, the Arduino commands the servo motor to return to its original position, lowering the barrier to stop unauthorized tailgating. If an unrecognized card is presented, the system displays an access denied message and keeps the servo motor closed. The entire circuit is wired on a breadboard using jumper wires and is powered by a reliable external power supply to ensure stable operation of the motor, display, and microcontroller.