Tentacled snakes-inspired flexible pressure sensor for pain sensation monitoring

Abstract Exploration of flexible tactile sensors with high sensitivity that can imitate the perception functions (tactile sensing and pain sensing) of human skin is the main force in the realization of electronic skin. The research of electronic skin with the function of pain perception is of great significance in the field of biomimetic robot and treatment of patients losing the pain sensation ability of their skin. Herein, to broaden the application field of traditional electronic skin, we demonstrate a biomimetic and highly sensitive tactile sensor for realization of sensory functionalities of human skin. The structure of our sensor mimics the surface of the tentacles of tentacled snakes, which are strikingly sensitive mechanoreceptors. We design a tentacle-inspired flexible sensor by sandwiching the convex dielectric layer of PDMS/MXene microarrays between two flexible electrodes. It is found that the bioinspired sensor exhibits a high sensitivity of 3.61 kPa-1, a fast response time of 29 ms and a satisfactory stability, ensuring the ability in monitoring physiological signals. Finally, we present the application of the sensor for finger bending, international Morse code detection, and artery pulse detection. By presetting the pain thresholds of different areas of skin in a program, the sensor can identify and distinguish pressure data that exceed the pain threshold, realizing the detection of pain. In addition, it can be further applied on robot skins to assess the risk level of the working environment by monitoring its pressure data.