Smart wireless flexible sensing system for unconstrained monitoring of ballistocardiogram and respiration

The ballistocardiogram (BCG) represents a promising unconstrained method for capturing cardiac vibrations, effectively mitigating the discomfort and activity limitations often associated with traditional long-term healthcare monitoring. Herein, we introduce a smart wireless flexible sensing system designed for the unconstrained monitoring of BCG and respiration. The core component of the system is a flexible pressure sensor featuring a gradient spherical crown microstructure design, which ensures high sensitivity to weak dynamic pressure signals even under high static pressure. This sensing capability enables the sensor, attached to the seat, to accurately capture subtle physiological signals from seated individuals. Furthermore, the system holds potential for assisting in the diagnosis of heart rate variability, providing new insights into the application of flexible sensors in the realm of unconstrained human health monitoring.