A Low-Cost Multi-Node Architecture with ESP32 Microcontrollers for Assisted Home Automation of Elderly and Disabled Residents

Pérez-Ayala P.C.; Salvador-Boza L.D.; Lopez-Lopez M.A.; Soto-Oroya C.A.; Cabana-Cáceres M.R.; Castro-Vargas C. · EAI Endorsed Transactions on Internet of Things (2025) · DOI: 10.4108/12871

Resumen

INTRODUCTION: Elderly and disabled populations worldwide are growing faster than care systems can absorb them, creating strong demand for affordable home-automation tools that let residents remain safe at home without continuous caregiver presence. Most low-cost IoT prototypes reported in the literature cover only one or two functional subsystems and send alerts to a single recipient, leaving a practical gap for multi-subsystem, multi-recipient solutions. OBJECTIVES: To design, build, and test a modular home-automation system that brings together four specialised sensor nodes—radio-frequency access control, ultrasonic proximity detection, combustible-gas monitoring, and rain-triggered physical protection—plus a fifth node combining multi-recipient alert coordination with remote lighting control across five areas of the dwelling, all over a coordinated wireless network with real-time alerts sent to multiple users simultaneously. METHODS: A waterfall lifecycle combined with test-driven development guided component selection and firmware coding. Five ESP32 microcontrollers exchange data through a lightweight publish-subscribe protocol; each node handles its own control logic and actuator independently, while a companion mobile application allows remote supervision and manual override. RESULTS: All four subsystems were functionally validated through virtual simulation followed by physical demonstration on a scale dwelling model: the RFID module granted or denied access correctly for authorised and unauthorised cards, the ultrasonic module opened and closed the back door in response to detected presence, the gas sensor triggered visual, audible, and remote alerts above the configured threshold, and the rain sensor activated the laundry-protection servo on detected precipitation. The Telegram notification channel delivered alerts to the user with an observed average response time of under two seconds. Total component cost came to approximately 73 United States dollars, far below comparable commercial products. CONCLUSION: The five-node distributed architecture demonstrates functional feasibility and meets the cost target needed for practical use in urban homes in developing countries, and offers a reproducible testbed for future assistive-technology research that includes controlled reliability and latency testing.

Instituciones: Universidad Nacional Federico Villarreal