Design, Simulation and Validation of a Microcontroller-Based Multi-Parameter Physiological and Environmental Monitoring System for Asthma Care

Abstract

Asthma management requires monitoring of physiological conditions and environmental factors that may contribute to symptom worsening. This study presents the design, simulation, and validation of a microcontroller-based physiological and environmental monitoring system for asthma care. The system monitors body temperature, pulse rate, electrocardiography (ECG), room temperature, room humidity, and air quality using LM35, MAX30100, AD8232, DHT11, and MQ-35 sensors, respectively. An ESP8266 microcontroller was used for sensor integration and data processing, while an LCD provided local display of the measured parameters. The sensors were validated against a digital thermometer, thermo-hygrometer, Polar H10, and multi-gas analyzer. The results showed generally good agreement with the reference instruments, with mean absolute differences of 0.18 °C for the LM35, 0.33 °C for DHT11 temperature, 0.23% for DHT11 humidity, 0.19 bpm for MAX30100 pulse rate, 0.87% for MQ-35 air quality, and 2.17bpm for the ECG sensor. The complete system was simulated in Proteus and successfully demonstrated simultaneous monitoring of the selected physiological and environmental parameters. The findings indicate that the proposed system provides a low-cost platform for monitoring conditions relevant to asthma care. However, it is not intended to diagnose asthma or determine disease severity. Incorporating respiratory rate, SpO₂, peak expiratory flow, wheeze detection, and clinical validation in future work could enhance its application to dedicated asthma monitoring.