Development of a piezoelectric polyvinylidene fluoride (PVDF) polymer-based sensor patch for simultaneous heartbeat and respiration monitoring

This study reports a piezoelectric polyvinylidene fluoride (PVDF) polymer-based sensor patch for simultaneous heartbeat and respiration detections. The principle is based on the piezoelectric sensing mechanism to detect the pulsatile vibrations, and periodical deformations on the chest wall of human body during heartbeats and respirations, respectively. In this study, the sensor patch with a structurally curved PVDF film was designed, and fabricated. The role of the curved structure design to enhance detection signals, and the capability of the sensor to faithfully detect the heartbeats and respirations were experimentally evaluated. Results revealed that the design of curved structure of PVDF film was capable of increasing detection signal by 151% for the respiration measurements compared with its flat counterpart. Moreover, the sensor was proved to be able to generate the heartbeat and respiration signals which were in concordance with those based on a commercial electrocardiogram (ECG), and respiratory effort transducer, respectively. Finally, the heart rate and respiratory rate measured through the sensor patch were proved to have no statistical significance compared with the reference data obtained from the ECG, and respiratory effort transducer-based detections, respectively. As a whole, this study has developed a PVDF-based sensor patch which was capable of monitoring the heartbeats and respirations with high fidelity. Other distinctive features include its small size, light weight, ease of use, low cost, and portability. All these make it a promising sensing device to monitor heartbeats and respirations either in medical centers, or home care units.