Design and implementation of a portable long-term physiological signal recorder

Area of Science:

• Biomedical Engineering
• Wearable Technology
• Physiological Monitoring

Background:

• Portable physiological recorders are essential for long-term health monitoring outside clinical settings.
• Existing devices often face limitations in battery life and electrode compatibility.
• There is a need for robust, low-power wearable devices capable of continuous physiological data acquisition.

Purpose of the Study:

• To design and implement a portable physiological signal recorder with extended operational time.
• To enable continuous measurement of electrocardiography, bioimpedance (for respiration), and activity.
• To evaluate the device's performance with different electrode types and during various physical activities.

Main Methods:

• Development of a low-power portable device integrating electrocardiography, bioimpedance, and a 3-axis accelerometer.
• Testing the device's functionality against reference signals and during dynamic movements and light exercise.
• Conducting a 24-hour continuous measurement to assess real-life performance.
• Evaluating the system's compatibility with both standard Ag/AgCl gel-paste electrodes and custom textile electrodes.

Main Results:

• The implemented portable recorder successfully measured electrocardiography, bioimpedance, and activity.
• The device achieved a 24-hour operating time, meeting the design goal.
• Both Ag/AgCl and textile electrodes were functional, though textile electrodes showed higher sensitivity to movement artifacts.
• The device demonstrated reliable operation during vigorous movements and light exercise.

Conclusions:

• The developed portable physiological signal recorder is a viable tool for extended monitoring.
• The device's low power consumption and multi-signal capability make it suitable for long-term wearable health applications.
• Further development may focus on mitigating movement artifacts with textile electrodes for enhanced usability.