Fabrication and Evaluation of Sensor for Measuring Pulse Wave Velocity using Piezo Film and Conductive Textile

Abstract

Arterial stiffness is causing the serious problems for human who is suffered from hypertension and metabolic syndrome. So it is important that measure the arterial stiffness for early prevention. Many researches point out that pulse wave velocity(PWV) is the reliable and simple method to predict arterial stiffness. In this paper, we developed the sensing parts that detect the pulse wave and ECG by using piezoelectric film and conductive textile with elastic band. Our system could detect 3ch pulse wave and ECG. Simultaneously, our algorithm extracts the features for calculating the delays among pulse waves. The delays are the significant parameter to estimate PWV, thus we design the experiment for evaluating the performance of our sensing parts. The reference is PP-1000(HanByul Meditech, Korea) that is good for performance evaluation. As a result, the start point of the pulse wave was the most reliable feature for comparing with PP-1000(r=0.691, P=0.00). The results between two operators showed that there is only a slight difference in the reproducibility of the devices. In conclusion, we assume that the suggested sensor could be more comfortable and faithful method for arterial stiffness.

Development of pulse diagnostic devices in Korea

“…Pulse diagnostic devices in Korea have used piezoelectric devices, 31 , 32 , 33 piezoresistive strain gauges, 34 , 35 , 36 , 37 air-vibration-detecting condenser microphones, 38 , 39 optical fiber transducers that use the reflective optical power change according to infinitesimal displacement, 40 optical fiber coupling controlled by infinitesimal displacement, 41 , 42 optical coherence tomography devices using in-line Michelson interferometers, 43 , 44 , 45 , 46 fiber Bragg gratings, 47 magnetic junction elements, 48 magnetic Hall devices, 49 , 50 , 51 , 52 , 53 , 54 , 55 moving pulse images, 56 , 57 and so on.…”

“…Recently, piezoresistive strain gauges and magnetic Hall devices have been used in the pulse diagnostic devices, and a system with a piezoelectric film sensor and conductive textile has been reported. 33 Table 1 lists directly measured physical parameters according to the sensor types.…”

“…To be able to realize traditional Korean medical pulse diagnosis, these technical issues need to be solved. Solutions can involve the research and development of a robotic arm or air pressure control system combined with multichannel piezoelectric films, conductive textiles, 33 , 196 or array sensors. 37 , 61 , 197…”