Comparative study on the measurement of human thermal activity

Abstract

Human physiological signals measurement is the necessity of today's modern world. The physiological signals, including heart rate, skin conductance, temperature, and pupil diameter, are significant indicators of underlying problems or illnesses and aid in indicating the underlying condition non-invasively. This study highlights the importance and needs for only one physiological signal, which is the body temperature as even a minor change in temperature values has a unique effect on the body. Hence, the present study focuses on comparing two well-known temperature sensors, namely DS18B20 and LM35, which are among the top choices for many temperature-based applications. The two sensors are compared in terms of cost, accuracy, temperature range, voltage, output type, implementation, packaging and required signal conditioning circuitry. The sole purpose is to find the adequacy of only one in terms of medical applications. The temperature readings are collected for 15 seconds from 10 participants between the age of 25-28 years and the data is sent to a microcontroller, which is Arduino Mega board. The microcontroller board processes the data for noise and artefacts removal and displays the final temperature readings on the serial monitor of Arduino IDE. The results highlight that DS18B20 is more accurate and robust in comparison to LM35, as it has lower fluctuations in the readings and is not affected by user movements. This study will help in the future development of healthcare systems, which may track the user's thermal changes accurately in real-time.