Relationship between Contact Pressure and Motion Artifacts in ECG Measurement with Electrostatic Flocked Electrodes Fabricated on Textile.

To develop a wearable multi-lead electrocardiogram (ECG) measuring system, we fabricated the electrodes and wires by using electrostatic flocking technology on a textile. By using this technology, it was possible to fabricate many electrodes and wires, simultaneously. Also the flocked electrodes and wires had stretchability and washing resistance properties. To use dry electrodes, it is important to reduce the influence of motion artifacts (MAs). The results of the experiment with the skin phantom revealed that the contact pressure between the skin and the electrode is an important factor in MA reduction. Then, we conducted experiments with a human body to determine the relationship between the contact pressure and the MAs. Under the pressures of 200 Pa and 500 Pa, MAs were observed. Meanwhile, under the pressures of 1000 Pa, 2000Pa and 4000 Pa, the ECG signals under rest and deep breathing conditions were able to be measured without MAs. Considering the comfortability, the contact pressure from 1000 Pa to 2000 is preferable. Finally, we fabricated the wearable ECG measuring system and succeeded in measuring 18-lead ECG signals. The measured ECG waveform is in good agreement with the ECG waveform measured by a commercial system.