A novel flexible pressure sensor array for depth information of radial artery

Abstract

Pulse wave collection from multi-points of radial artery under different static pressures is an essential method to diagnose diseases. However, there are some problems in the currently-used measuring instruments. Single-type sensor has limitations to pulse wave acquisition. It is not enough to set three sampling points to detect variation trend of radial artery pulse wave. Adaptation to different wrist surfaces and mutual interference of sensors are neglected. This paper proposes a novel flexible compound pressure sensor array for measuring radial artery pulse wave to overcome the problems mentioned above. Our compound pressure sensor consists of a piezoelectric sensor and a piezoresistive sensor which are used to measure pulse wave and static pressure separately. A bending structure of the sensor could guarantee the signal intensity and prevent the occurrence of inverted waveform. In this study, poroelastic materials are used to achieve flexible connection and decrease interference among sensors. In addition, the amplitude characteristics of pulse wave in radial artery are described and the arrangement and size of the sensor array is designed based on statistical data. Anti-interference, repeatability and validation experiments are carried out to evaluate the performance of the sensor array. The results show that the flexible compound pressure sensor array not only reflects depth information of radial artery pulse wave under a wide range of static pressures, but also has good repeatability and anti-interference performance.