Microcontroller-Based Home Automation System Using Bluetooth Communication

Abstract

Home automation provides a practical way to improve convenience, accessibility, safety, and energy management by allowing electrical appliances to be controlled through embedded electronics. This methodology paper presents the design and evaluation framework for a low-cost microcontroller-based home automation system in which an Android mobile device communicates with a local controller through Bluetooth. The proposed architecture uses an HC-05 class Bluetooth serial module, an ATmega328P microcontroller, transistor/relay driver stages, isolated electromechanical relays, and a simple mobile command interface. The methodology emphasizes reproducibility: requirement definition, hardware integration, command coding, pairing and authentication, firmware state handling, load switching, feedback indication, and structured performance tests. The principal evaluation variables are command success rate, response time, usable communication range, relay switching reliability, and recovery from invalid commands. The design is grounded in established Bluetooth, microcontroller, Android, and wireless-home-automation literature published no later than 2017. A representative validation dataset is included to demonstrate the proposed analysis procedure; it is explicitly presented as methodology-demonstration data rather than a claim of newly measured laboratory results. The resulting framework is suitable for student prototypes and small residential installations where low cost and local, Internet-independent control are priorities.