A novel bed-based ballistocardiography system for non-contact monitoring of vital signs, apneas and arrhythmias via smartphone integration

Abstract

This work presents a novel remote ballistocardiography system designed for continuous monitoring of individuals lying in bed. The system utilizes video recordings of a tracking marker placed on the side of the mattress. By processing the motion of this marker, ballistocardiographic waveforms are generated, capturing mattress displacements caused by cardiac activity, respiration, and body movements. The longitudinal and transverse axes of the mattress naturally separate the contributions of cardiac and respiratory signals within the ballistocardiography waveform. This orthogonal separation enables the independent analysis of each component, thereby enhancing the accuracy of heart and respiratory rate estimations. The system’s high resolution and sensitivity enable not only the reliable extraction of the subject’s vital signs, but also the detection of activity episodes—both voluntary and involuntary—alongside physiological anomalies such as sleep apnea and cardiac arrhythmias. The simplicity of the proposed setup offers significant advantages over conventional ballistocardiography systems by eliminating the need for integrated sensors and periodic calibration, and by mitigating common challenges in remote ballistocardiography applications, including susceptibility to ambient lighting conditions.