Design And Implementation Of Real-time Monitoring System For Astronaut's Physiological State

With the continuous development of space technology in China,the demand for real-time monitoring of astronauts’ physiological status has become increasingly prominent.In this thesis,a wearable multi-physiological acquisition system is designed and implemented.Ballistocardiogram signal,electrocardiogram signal and blood oxygen pulse wave signal are collected by this system.This project mainly focuses on the evaluation of the physiological status of astronauts and the research on ballistocardiogram signal.The main contents of this thesis are summarized as follows:(1)A multi physiological signal acquisition system is realized.The three physiological signals are collected synchronously,and the acquisition system is tested in three aspects:wear comfort,system power consumption and signal quality.It would provide the hardware basis for signal processing and analysis.(2)The methods of signal processing and analysis are explored.In software layer,the signal processing method with low complexity and good real-time performance is used to filter noise,and then three kinds of signal are displayed in software layer.In the subsequent signal analysis,in order to make the signal analysis more accurately,the filtering noise algorithm based on EMD and Hilbert transform is used.The template matching algorithm is used to extract the features of ballistocardiogram signal.(3)The application of ballistocardiogram signal is explored in this thesis.The blood pressure could be calculated by pulse wave transit which is extracted through ballistocardiogram signal and pulse wave signal.Heart rate variability in time domain and frequency domain indexes of electrocardiogram and ballistocardiogram signal are compared,the method of heart rate variability analysis based on ballistocardiogram signal is explored.(4)Experiments are designed to verify the effect of the acquisition equipment,the methods of signal processing and signal analysis.Experiments are conducted to verify the effectiveness of the algorithm for filtering noise,feature point extraction and heart rate variability analysis.The correlation between the signals collected by different sensors is verified by comparing experiments with different sensors.The application prospect of cardiac function is explored by designing experiments.Through the research,we have achieved the following results:(1)multi physiological signal acquisition system is realized;(2)signal processing and joint analysis methods are established;(3)the medical application prospect of ballistocardiogram signal is explored.