Relationship between motion artifacts and fiber length of a flocked electrode in electrocardiogram measurement

Abstract

In this paper, we report on the relationship between the fiber length of flocked electrodes and the motion artifacts (MAs) that occur in electrocardiogram (ECG) measurements. During ECG measurements, fluctuations in the ECG baseline are observed when slippage occurs at the skin-to-flocked electrode interface. We evaluated the friction behavior and MAs characteristics of four types of flocked electrode with various fiber lengths (0.3 mm, 0.5 mm, 0.7 mm, and 1.2 mm). As a result, it was confirmed that the longer fiber lengths for the flocked electrodes provided more stable contact with the skin phantom. The correlation coefficients between the ECG waveform without MA and the ECG waveform using each fiber length (0.3 mm, 0.5 mm, 0.7 mm, 1.2 mm) were 0.58, 0.58, 0.81, and 0.91. Since the correlation coefficient close to 1 means less MA, it was shown that the longer fiber length, the higher the MA reduction effect. We also conducted an ECG measurement experiment using an ECG measurement chest band. When the flocked electrode with the 1.2-mm-long fibers was used, the ECG signal was measured successfully with only small MAs from body movements caused by respiration.