A Design Of Multi-Physiological Parameters Monitor Based On Smart Glasses

With the improvement of living standard,the incidence of chronic diseases such as hypertension and obstructive sleep apnea-hypopnea syndrome(OSAHS)is increasing annually.The long-term monitoring of blood pressure and blood oxygen saturation is an effective way to prevent the incidence of these diseases.There are a lot of portable health monitoring devices on the market,but few are involved with multi physiological parameters monitoring.In this paper,a multi-physiological parameter monitor was designed based on a pair of smart glasses,which can conduct long-term health monitoring and is pretty suitable for daily monitoring.This device can not only detect multiple physiological parameters including systolic blood pressure(SBP),diastolic blood pressure(DBP),heart rate(HR)and blood oxygen saturation(SpO2),but also display the single lead electrocardiogram(ECG)and pulse wave(PPG)in real time.In this paper,two aspects of work are completed:First,the relationship between pulse wave transit time(PTT)and blood pressure was discussed.PTT refers to the time required for a pulse wave to travel from heart to peripheral blood vessels during a cardiac cycle.Some researches indicate that there is a good linear correlation between PTT and SBP,but not with DBP.To solve this problem,a nonlinear relationship between PTT and SBP or DBP is derived based on recent research.Second,a complete system of multi physiological parameters monitor,which includes signal acquisition circuit,MCU control circuit,BLE 4.0 protocol stack,Android client and algorithm,is designed based on the improved PTT-BP model and the method of dual wavelength spectrum.The system is used to experiment on 30 people.The results show that the measured physiological parameters of this system are in good agreement with the results measured by the standard instruments which means this system can be used for detection of hypertension and OSAHS disease and daily physiological monitoring.