Wireless Wearable Respirator for Accurate Measurement of Breathing Parameters

Abstract

This paper presents iMask, a non-invasive and cost-effective wireless wearable respirator that measures breathing parameters in real time. The system consists of a wireless wearable respirator as well as a signal processing pipeline that runs inside the respirator, and provides a Bluetooth Low Energy (BLE) interface for applications. By sensing the airflow temperature at the exhalation valve of respirator with NTC series resistors, the breathing parameters of each respiratory cycle can be measured regardless of breathing pathways through nose or mouth. iMask takes advantage of a voltage divider with controllable divider resistors to enhance the measuring sensitivity of temperature, and a peak and valley detection algorithm with spline interpolation to increase sampling period without reducing detection accuracy. The experimental results show that the breathing parameters can be accurately measured with a mean absolute error (MAE) of 0.29 beats per minute (bpm) for respiratory rate. As a low cost, reusable, comfortable and low power wearing device for breath monitoring, iMask holds promise in real-world feasibility.