Touchless Dual-Mode Smart Door Lock System Using Smartphone Authentication and Bluetooth-Enabled Arduino with Solenoid Actuation

Abstract

The rapid spread of infectious diseases such as COVID-19 has significantly increased the demand for touchless and secure access control systems. Traditional locking mechanisms and even fingerprint-based biometric systems require physical contact, which may facilitate the transmission of pathogens. To address this issue, this project presents a touchless smart door locking system that integrates smartphone-based authentication with Bluetooth communication. The system is developed using an Arduino Nano, HC-05 Bluetooth module, and a solenoid door lock. Instead of directly using a physical fingerprint sensor, the system leverages the smartphone’s built-in biometric authentication, allowing users to unlock the door without physical contact. Once authenticated on the mobile device, a secure command is transmitted via Bluetooth to the Arduino controller, which processes the signal and activates the solenoid lock mechanism. This dual-mode approach enhances both security and convenience by combining biometric verification with wireless control. The proposed system is cost-effective, easy to implement, and suitable for residential, office, and institutional applications. It also supports multiple users and ensures reduced human contact, thereby contributing to improved hygiene and safety standards in access control systems.