A Novel Forced Oscillatory Device Designed For Monitoring Respiratory Impedance

More attention has been paid on health with the quick development of modern society,respiratory disease has become a more and more important threaten to human health. Greatly panic was caused by the bird flu、Severe Acute Respiratory Syndrome(SARS) and A(H1N1) influenza in the society in the last few years.They have greatly relationship with breathing important organ--lung,so it was an important meaning that early prevention and treatment to lung tissue.Although medical and health services made great progress in domestic in the past few years,the development of medical equipments were relatively lagged. A new and noninvasive respiratory impedance monitoring was designed based on forced oscillation technique,the noninvasive method detected the lung tissue by mouth or nose mask.Theory modeling、module block division and clinical test method was adopted to develop the original prototype which was divided into oscillation generator module, data acquisition module, data analysis module and data display module.Oscillation generator module used the voice coil motor as the core of the servo control system which adopted forward control double closed loop strategy, low magnitude and frequency sine signal was provided in the new forced oscillation technique method;Hardware low pass filter and digital software filtering method was applyed in order to collect the press and flow signal of the pipe by STM32in the data acquisition module; The optimal linear approximation method and correlation method which was the time domain data analysis algorithm was taken in order to diagnosis the situation of lung organ by analysising respiratory resistance、impedance、 respiratory reactance parameters and their waveforms and modified correlation coefficient criterion was proposed in order to judge the effectiveness of the data in data analysis module;Parameters and waveforms were displayed in VGA screen by button operation;lastly assembled prototype reached monitoring the significance of the lung condition in hospital by R-I-E model and volunteers test clinical experiments...