The Development Of Wearable Automatic Pressurizing Pulse Diagnosis Bracelet

Pulse diagnosis is the experience summary of long-term medical practice of Traditional Chinese Medicine(TCM)and it is an important part of the four diagnosis of TCM.Thus,the acquisition,analysis and processing technology of pulse signals is an important research content of objectification of pulse diagnosis.However,most of the common clinical pulse diagnosis instruments have some problems,such as poor portability,high cost,incapable automatic pressurization and so on.In order to solve these problems,this paper developed wearable automatic-pressurized pulse diagnosis bracelet pressurizing based on the pulse diagnosis theory of TCM,combined with the concept of mobile medicine and intelligent medicine.Firstly,this paper designed the bracelet hardware using nrf52832 as the control core.According to the characteristics of pulse signal,the signal conditioning module and the signal transmission module based on Bluetooth Low Energy are designed to ensure the accuracy of pulse signal acquisition.Then the pressurization module is developed based on stepping motor and the mechanical structure is designed by measuring and analyzing the position of wrist section of radial wrist artery.In addition,the calibration experiment of the pulse signal acquisition system is performed to calibrate the digital pulse signal.In the part of hardware design,performance,power consumption,volume and other requirements are fully considered to make the bracelet meet the requirements of lightweight,portable and low power consumption.Secondly,the software of bracelet is developed,including upper and lower computer program.Based on nrf52832,the lower computer developed the signal acquisition module,motor control module,power management module and Bluetooth data transmission module.Under the premise of ensuring the accuracy of signal acquisition,it effectively improved the sampling frequency and reduced the power consumption.The Android APP is developed on the upper computer.It consists of Bluetooth communication module,data storage module,automatic pressurization module and pulse signal analysis and processing module.It can collect and store pulse signal efficiently and reliably.The method combined rough pressuring and fine pressuring is presented to automatically obtain the best pulse-taking pressure and realize best pulse signal acquisition.Finally,the pulse signal analysis and processing module in the upper computer APP is designed and developed,which realizes the preprocessing,feature extraction and classification of the pulse signal.Based on Butterworth band-pass filter and cubic spline interpolation,the pulse signal is filtered and its baseline drift is removed.Then the sample entropy,multi-scale entropy and time-domain characteristics of pulse signal are extracted,and the pulse signal classification and recognition model is established based on SVM.The model is imported into the upper computer app software,and the pulse signal analysis and processing program is designed to detect cardiovascular health status.