Wearable multichannel-active pressurized pulse sensing platform.

With the modernization of traditional Chinese medicine (TCM), creating devices to digitalize aspects of pulse diagnosis has proved to be challenging. The currently available pulse detection devices usually rely on external pressure devices, which are either bulky or poorly integrated, hindering their practical application. In this work, we propose an innovative wearable active pressure three-channel pulse monitoring device based on TCM pulse diagnosis methods. It combines a flexible pressure sensor array, flexible airbag array, active pressure control unit, advanced machine learning approach, and a companion mobile application for human-computer interaction. Due to the high sensitivity (460.1 kPa-1), high linearity (R 2 > 0.999) and flexibility of the flexible pressure sensors, the device can accurately simulate finger pressure to collect pulse waves (Cun, Guan, and Chi) at different external pressures on the wrist. In addition, by measuring the change in pulse wave amplitude at different pressures, an individual's blood pressure status can be successfully predicted. This enables truly wearable, actively pressurized, continuous wireless dynamic monitoring of wrist pulse health. The innovative and integrated design of this pulse monitoring platform could provide a new paradigm for digitizing aspects of TCM and other smart healthcare systems.

Fully printed minimum port flexible interdigital electrode sensor arrays.

Screen-printed interdigital electrode-based flexible pressure sensor arrays play a crucial role in human-computer interaction and health monitoring due to their simplicity of fabrication. However, the long-standing challenge of how to reduce the number of electrical output ports of interdigital electrodes to facilitate integration with back-end circuits is still commonly ignored. Here, we propose a screen-printing strategy to avoid wire cross-planes for rapid fabrication of flexible pressure sensor arrays. By innovatively introducing an insulating ink to realize electrical insulation and three-dimensional interconnection of wire crossings, the improved sensor array (4 × 4) successfully reduces the number of output ports from 17 to 8. In addition, we further constructed microstructures on the laser-etched electrode surfaces and the sensitive layer, which enabled the sensor to achieve a sensitivity as high as 17 567.5 kPa-1 in the range of 0-50 kPa. Moreover, we integrated the sensors with back-end circuits for the precise detection of tactile and physiological information. This provides a reliable method for preparing high-performance flexible sensor arrays and large-scale integration of microsensors.