Design And Implementation Of High Precision Digital Electronic Sphygmomanometer Based On STM32

With the development of society,people are paying more and more attention to their physical health.At present,hypertension has become a major disease that harms the health of middle-aged and elderly people.Therefore,it is extremely important to measure your blood pressure regularly and understand the trend of your body's blood pressure.A variety of electronic sphygmomanometers exist on the market today,which have the advantages of small size,convenient carrying,and simple use,but also have problems of high price and inaccurate measurement.In order to further improve the accuracy of electronic sphygmomanometer measurement,this subject is based on the CONTEC08 A sphygmomanometer produced by Kang tai Company.In terms of hardware,the STM32L433 VC of STMicroelectronics was used to realize the control function of the electronic sphygmomanometer;in the blood pressure signal acquisition,the high-precision ADS1291 digital-to-analog conversion chip and the MPS2107 pressure sensor were used instead of the PSG010 pressure sensor.The pressure acquisition module consisting of a preamplifier,a band pass filter and a power amplifier can directly transmit the original blood pressure waveform to the STM32 for software filtering,which not only improves the accuracy of the collected data,but also avoids the hardware filtering.Distortion caused by blood pressure waveforms.In software,by analyzing the characteristics of blood pressure waveform separation,the integral coefficient filter is designed to separate and noise reduction the blood pressure waveform collected by the pressure acquisition unit,and compare with the filtering effects of the classic filters IIR and FIR.The results show that the integer coefficient filter not only has a fast calculation speed,but also filtering effect is better than other methods.The pulse wave and the static pressure wave are obtained after filtering and separating the blood pressure waveform using the integral coefficient filter.After the pulse wave is de-interfered by the graphic contrast method,the waveform feature method and the amplitude coefficient method are used to determine the systolic pressure and the diastolic pressure.This subject uses Visual C++ to design the upper computer program to collect blood pressure waveforms,and uses Matlab to perform waveform separation and error analysis on the collected signals,and has carried out rigorous tests.Dynamic blood pressure values and waveforms were detected by oscillometric method and system simulation,respectively.The program was compiled and burned into the STM32 chip by IRA.Finally,the blood pressure measurement was performed on 25 people using the product.The measurement results were compared with the international current standard auscultation measurement results.The data obtained by the two measurement methods were not significantly different.And has a good consistency.It has been verified that the product has improved in measurement accuracy and can reflect the real situation of human blood pressure.