A Corrugated PVDF-Based Flexible Piezoelectric Sensor for Physiological Signal Detection.

Area of Science:

• Materials Science
• Biomedical Engineering
• Sensor Technology

Background:

• Continuous monitoring of heart rate and respiration is crucial for disease diagnosis and health management.
• Flexible polyvinylidene fluoride (PVDF) piezoelectric sensors offer accurate physiological signal acquisition.
• Existing high-performance PVDF sensors often involve complex fabrication and composition control challenges.

Purpose of the Study:

• To develop a flexible piezoelectric sensor for contactless physiological signal monitoring.
• To enhance sensor performance through a novel corrugated film design and elastic encapsulation.
• To demonstrate the sensor's capability in detecting subtle physiological movements.

Main Methods:

• Fabrication of a corrugated polyvinylidene fluoride (PVDF) film (CPF) using a simple template molding method.
• Encapsulation of the CPF in a soft elastomer to maintain its wavy geometry and enhance deformation.
• Integration of the sensor with a soft cushion for noncontact monitoring of thoracic and cardiac movements.

Main Results:

• The corrugated PVDF film sensor (CPF-based sensor) demonstrated improved piezoelectric output and dynamic response.
• Achieved a sensitivity of 0.36 V/N, a minimum detectable force of 98 mg, and response/recovery times under 0.1 ms.
• Successfully detected subtle thoracic and cardiac vibrations and captured pulse waveforms at multiple body locations.

Conclusions:

• The developed corrugated PVDF film sensor offers a promising approach for noncontact physiological signal monitoring.
• The unique wave design and elastic encapsulation synergistically enhance sensor performance.
• The sensor's ability to detect subtle physiological signals highlights its potential for advanced health management applications.