Development of microcontroller based Body Mass Index machine

Abstract

An essential diagnostic tool for monitoring body mass distribution with the associated health implications in humans is a Body Mass Index (BMI) machine. This widely used metric for body mass is derived from measuring human height and mass which its manual/orthodox determination is very tedious and prone to errors. This study developed a microcontroller based BMI machine for automatic, accurate, interactive monitoring means of human health. The system design was achieved through Proteus 8.9 electronic simulation application software and, the development was actualised through construction using soldering, fitting, and coupling of electronic components. Body mass load cell in a Wheatstone format with HX711 and ultrasonic based (HC_SR04 sensor) were utilised for capturing mass and height. The machine is controlled by Arduino microcontroller programmed in C language to calculate the BMI and provides confidential result (interpretation) through a dedicated SIM card of GSM Module SIM900L to a medical practitioner. The system automatically output user’s BMI parameters and value on a Liquid Crystal Display (LCD) and include BMI interpretation as text for medical diagnosis to a dedicated doctor’s line. The system was accurate, reliable and can be adopted as a screening tool for obesity and other related diseases.