Multi-Modal Flexible Headband for Sleep Monitoring

Sleep is essential for health, with poor-quality sleep may link to cognitive impairment, increased disease risk, etc. Traditional sleep monitoring systems, such as polysomnography(PSG), are comprehensive but costly, uncomfortable, and confined to clinical settings. Recent wearable sleep monitoring devices typically employ single-channel EEG signal from the forehead, which can only acquire single-modal signals and may limit the accuracy of sleep analysis to some extent. To address these issues, this paper proposes a low-cost, multi-modal, wearable and comfortable headband system for sleep monitoring. The headband integrates six EEG sensors, a six-axis inertial measurement unit (IMU) and a temperature sensor to collect EEG signals, motion data, and environmental temperature, and can also derive information from other modalities such as heart beat, respiration rate, body movement, etc. The headband system integrates multiple sensors, with the EEG sensors primarily using flexible claw-shaped dry electrodes that penetrate the hair to make sufficient contact with the scalp for precise detection of minute signals. This system provides a wealth of multi-modal information, which offers a solution for precise sleep analysis and the identification of sleep disorders such as insomnia and sleep apnea. To verify the performance of the headband prototype, comprehensive experiments were performaed as compare to PSG. Experimental results show that the Pearson correlation coefficient of EEG signals can reach 0.9435, and the RR interval derived from IMU is only 0.001 seconds different from that obtained from PSG ECG signals, proving a high consistent with the standard results measured by PSG.