Fabrication of an Automatic Gate Control System with Number Plate Recognition for Residential Estates in Delta State

Security at the access points of residential estates in Delta State, South South Nigeria, is largely dependent on manual gateman operations that are susceptible to human error, fatigue, and corruption. This project presents the fabrication of an automatic gate control system that integrates optical character recognition for vehicle number plate identification with a motorized barrier gate actuator. A Raspberry Pi 4 single-board computer processes images from a USB camera mounted at the gate and runs an OpenCV and Tesseract OCR pipeline to extract number plate characters. Recognized plates are compared against an authorized vehicle database stored in a local SQLite database. Authorized vehicles trigger the barrier gate motor via a relay interface, while unauthorized vehicles generate a buzzer alert and log the event with a captured image. The system was installed and tested at a 60-residence estate in Asaba over a two-month period involving 148 registered vehicles. Plate recognition accuracy under daytime lighting conditions was 93.4 percent, dropping to 81.2 percent under night lighting, prompting the addition of infrared illumination as a system improvement. Average gate response time from plate detection to barrier opening was 2.1 seconds. Resident satisfaction surveys indicated strong acceptance of the automated system over the previous manual process. The study recommends cloud-based database synchronization for estates with multiple entry points. Keywords: number plate recognition, automatic gate, residential security, OpenCV, Delta State