Number Plate Detection System Using Computer Vision and Automatic Toll Collection

The Number Plate Detection and Automatic Toll Collection System is a computer vision-based project designed to automate vehicle identification and toll payment at toll plazas. The system uses Raspberry Pi 4B (4GB RAM) as the central processing unit, powered by a 5V 3A adapter and integrated with an Entry IR Sensor, an Exit IR Sensor, a Logitech C270 USB Camera (1280×720 resolution), a Servo Motor, an I2C 16x2 LCD Display, and an LED Indicator. When a vehicle approaches, the Entry IR Sensor triggers the USB Camera to capture the vehicle’s front image. OpenCV is used for number plate localisation and image pre-processing, and Tesseract OCR (configured with Page Segmentation Mode 8 and the LSTM engine) extracts the vehicle’s registration number from the cropped plate region. The detected number plate is first displayed on the web interface before any gate action is taken. The system then queries a three-table MySQL/SQLite database for owner details and applies the Haversine formula to GPS coordinates to determine if the owner resides within 10 km of the toll plaza; if so, the toll is waived, otherwise it is automatically deducted. The Servo Motor lifts the gate barrier, the I2C 16x2 LCD displays the transaction status, and the LED Indicator and Buzzer provide real-time feedback. The Exit IR Sensor detects vehicle departure and triggers gate closure. The system achieves Tesseract OCR precision of 90.81% and recall of 83.97%, with end-to-end operation completing in under 2 seconds per vehicle, significantly reducing manual intervention and enabling smart contactless toll operations.

Number Plate Detection, Automatic Toll Collection, Raspberry Pi 4B, Tesseract OCR, OpenCV, IR Sensor, Servo Motor

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