Study On Wearable Continuous Measurement Method Of Blood Pressure Base On Pulse Wave

With the increasingly serious threat to human health,hypertension has become the most important risk factor for cardiovascular and cerebrovascular diseases.It is important to monitor blood pressure continuously.Existing equipment for monitoring blood pressure interferes with people's daily life,due to its large size,heavy weight and complicated device,and an inflatable cuff.Therefore,it is of great significance to study the method of wearable blood pressure measurement which can not only affect the daily life of the subjects,but also can meet the requirements of comfort.Firstly,the method of blood pressure measurement based on pulse wave transmit time is selected,compared with other continuous blood pressure measurement.Based on the analysis of the formation mechanism and influencing factors of blood pressure and pulse wave,the relational model between pulse wave transmit time and blood pressure was established.Secondly,this paper studies the blood pressure detection algorithm based on pulse wave transmit time.The wavelet transform is used to filter the noise of ECG signal and the PPG signal.The differential double threshold algorithm is proposed to extract the feature points of ECG signals and pulse wave signal,which is validated by the MIT-BIH Database and MIMIC Database.Then,the calculation method of pulse wave transmit time and the parameter estimation method of the relational model between pulse wave time and blood pressure were analyzed.Then,through the analysis of the demand of wearable continuous blood pressure monitoring system,the sensor nodes are integrated by fabric electrode,photoelectric sensor,microcontroller and Bluetooth module were designed.Monitoring software developed on Android smartphone implements wireless data transmission and blood pressure monitoring.A kind of clothes for measuring physiological parameters was designed by using conductive fabric and 3D printing technology,which achieves the portability,comfort and reusability of wearable system.Finally,the clothes for physiological parameter measuring is used to simultaneously achieve ECG signal and PPG signal that are used to validate the algorithm of blood pressure measurement based on blood pressure measurement.The experiments are conducted to demonstrate the feasibility and effectiveness of the wearable continuous blood pressure measurement based on pulse wave.