Monitoramento de variáveis ambientais indoor: sistema embarcado de baixo custo para avaliação de conforto

Abstract

The consolidation of remote work (home office) has highlighted the lack of control over environmental quality in residential spaces, with direct implications for occupational health and productivity. This study aimed to develop and validate the technical feasibility of a low-cost embedded system, based on the Internet of Things, for monitoring thermal, acoustic, and luminous variables. The hardware architecture employed an ESP32 microcontroller integrated with the BME280, MAX9814, and TEMT6000 sensors, as well as DS3231 real-time clock, SD-card, and OLED display modules to ensure temporal integrity and data visualization. The methodology included cross-validation of the resistive sensors against reference mobile applications, applying regression adjustments to mitigate nonlinearities, in addition to exploratory data analysis and the development of an interactive analytical interface for dynamic visualization and operational diagnostics. The case study was conducted in a home office located in the city of Manaus, under an equatorial climate. Exploratory data analysis—supported by scatter plots, heatmaps, and temporal segmentation—confirmed the physical consistency of the prototype, revealing, through the correlation matrix, the expected thermodynamic trends among the monitored variables, such as the inverse relationship between temperature and relative humidity. The results indicated occurrences of afternoon thermal stress (elevated PMV), reinforcing the need to interpret indoor environmental performance in light of local climatological normals. It is concluded that the proposed tool is feasible for the intended application, offering sufficient sensitivity to identify environmental vulnerabilities and to support decision-making for improving workplace ergonomics.