Development Of 3D Printed Dry Electrodes And ECG Signal Acquisition Analysis

Standard commercial Ag/AgCl electrodes are widely used to monitor biopotential in modern clinic and biomedical applications.But there are inevitable limits:skin preparations before application is cumbersome and irritating.To solve the limitation,in this paper we develop a novel 3D printed dry electrode for biopotential recording.3D capable design software is used to draw the electrode model.Then resulting file is simply loaded on a 3D printer.The electrode is made by acrylonitrile butadiene styrene and copper wire.These electrodes are mechanical stable,reusable,low cost and conveniently applied.Impedance of our electrodes is acceptable.They have good performance in electrocardiograph signal recording compared with wet electrodes and can acquire typical electromyogram signal.Moreover,we develop a software applied to lab-made signal acquisition device,there are inevitably high frequency noise,baseline wander,power frequency interference and motion artifact during measurement,it requires a method to remove the noise while retaining details of ECG signals.By studying wavelet transform and analysing noise frequency domain,wavelet decomposition and reconstruction is proved an effective way.In order to learn more information about ECG,this paper proposes algorithms for QRS cluster detection.These functions,taking advantage of QRS cluster feature,are embedded in acquisition software,so that it would show heart rate in real time.Accurate R wave detection is foundation of HRV(heart rate variability)analysis as well.HRV is an important index to evaluate the physiological state of human body.It is concerned with nerve activity and could reflect balance between sympathetic and parasympathetic nerve.This paper attempts to find an approach for arrhythmia diagnosis accurately using HRV analysis.Measures in time domain,frequency domain and nonlinear domain had been examined with date from PhysioNet database,however,results were not so good as expected.After reviewing the development and applicants of nonlinear dynamics theory,this paper proposed the average coding length of ECG based on Hoffman coding,.A series of experiments showed this method is capable to diagnose arrhythmia with fidelity.