An IoT-Based Calculator for Body Mass Index Determination

This paper illustrates the creation of a portable Body Mass Index (BMI) calculator that uses ultrasonic sensors and load cells interfaced with a microcontroller to determine BMI automatically. The novelty of our system lies in its automation of real-time weight and height measurements, eliminating the need for manual input, and integrating data logging with cloud-based monitoring. Our system provides a sustainable and user-friendly solution for BMI determination, surpassing the drawbacks of manual approaches, even with load cell calibration and sensor alignment being intrinsically difficult problems. Ultrasonic sensors are used to detect height, and load cells are arranged in a Wheatstone bridge to measure weight. A microprocessor processes the data to compute BMI values. While the ultrasonic sensor determines height by timing the return of transmitted sound waves, the load cell determines weight by monitoring changes in electrical resistance under applied force. This automated, microcontroller-based BMI calculator encourages a healthy lifestyle and sensible weight management by being reasonably priced and flexible enough to work in a variety of settings, including isolated and resource-constrained locations. Our study aims to develop low-cost, effective BMI measurement equipment that can be used in a variety of scenarios. To ensure sustainability in terms of functionality and environmental effects, future work will focus on improving calibration techniques to increase accuracy and enable greater deployment. Our method seeks to enhance health monitoring and management in various communities by addressing the challenges of manual BMI estimates, particularly in resource-poor locations.