Comparative Evaluation of Flexible and Rigid Dry Electrodes Versus Gel Electrodes for Reliable ECG Monitoring in Android Wearable Smart Garment

Conventional silver/silver chloride (Ag/AgCl) gel electrodes are widely used in clinical settings due to their excellent signal quality. Long-term use can, however, lead to skin irritation. Reusable dry electrodes offer a promising alternative for wearable electrocardiogram (ECG) devices, potentially reducing hospitalization time and healthcare costs, especially for elderly individuals with sensitive skin. In order to address this need, we developed a smart garment integrated with novel dry electrodes for wireless ECG recording. The acquired ECG signals are transmitted via Bluetooth to a developed Android Smartphone application, “ECG Surveillance.” The application displays the heart rate (HR) alongside the ECG signal. An alert notification is triggered if the HR falls outside the normal range of [60, 90] beats per minute (bpm). The entire system is battery-powered, rechargeable, and designed for extended use. We experimentally validated the system on a male subject, comparing the performance of gel and dry electrodes during the specific movements outlined in our experimental protocol. Additionally, we developed an algorithm to assess the performance of each electrode type based on HR, sensitivity, and signal-to-artifact ratio (SAR). A novel artifact removal technique was also proposed.