Design And Application Of Flexible Textile Electrodes For Bioelectrical Signal Measurement

At present,the disposable gel electrode widely used in medical institutions can collect high quality biological electrical signals,but it is not suitable for long-term monitoring.To satisfy the requirements for wearable long-term monitoring,the ECG electrodes and acquisition systems should be lightweight,biocompatible,easy to use,comfortable to wear,and capable of maintaining good signal quality during daily activity and over a long period of time.In this paper,a new textile structure bioelectric dry electrode is prepared by the method of silver-plated yarn embroidery.Plating AgCl on the electrode surface with electrochemical deposition,and the electrochemical properties of the embroidered electrode were evaluated by the independently developed electrode performance test platform.Then the moisturized textile electrode was made with different base materials.By using electrodes with different water content to measure the electrocardiogram,the influence of electrode water content on the collection of electrical signals was discussed.Finally,the embroidered electrode was integrated into the clothing,four kinds of ECG belts were made with different materials.On the basis of this,the influence of interface pressure on the motion artifacts and noise in ECG was discussed.Ordinary textile dry electrodes have higher ac impedance than disposable gel electrodes,the grater impedance lead to the more the voltage value is obtained during the ECG signal collection process,which is not conducive to obtaining accurate electrocardiogram.Plating AgCl on the surface of embroidered electrode is beneficial to reduce the polarization impedance,and obtain the high quality electrocardiogram.The AgCl particles on the surface of embroidered electrode increased with the increase of electrochemical deposition time.However,the impedance of Ag/AgCl complex will increase when AgCl particles over-density.The experimental results show that the voltage is 2V,90s reaction time of Ag/AgCl electrode from electrochemical performance from the actual effect of ECG signal acquisition is the best choice.For the embroidered dry electrodes with different bases,the difference in retention performance of the base will affect the contact impedance between the electrode and the skin interface,the accuracy and intensity of the electrocardiogram signal are affected.Through the experiments,the embroidery electrode with polyacrylate nonwoven fabric has good water-retaining properties.The water in the electrode is moderate,there was no significant decrease in the quality of electrocardiogram detected in 10 hours.By adding different filler materials to the heart rate test band,it is shown that the pressure of the electrode and the skin interface can affect the electrical signal,especially the dynamic signal quality.In this project,the influence of AgCl content on electrode surface,textile electrode humidity and electrode-skin interface pressure on ECG acquisition can be strongly supported in the future for improving ECG monitoring of electrodes.