Real-time Monitoring of Human Breathing Using Wearable Tilted Fiber Grating Curvature Sensors

Respiration rate and volume are important physiological indicators of human health. They can indicate cardiovascular health status and cardiopulmonary function. Here, we demonstrate a compact breath monitoring system based on a wearable tilted fiber Bragg grating (TFBG) curvature sensor for human respiration monitoring. With the assistance of a custom designed breathing tube, TFBGs provide a very reproducible highly sensitive, real time response to curvature changes during respiration. The miniaturized and cost effective sensing system which we propose consists of a tunable laser module, a field programmable gate array acquisition control circuit module, and a sensor module. Different breathing patterns can be successfully identified from the optical amplitude and frequency output of the sensor. The robust instrument displays high repeatability and real-time tracking.