A Nature-inspired Hierarchical Branching Structure Pressure Sensor for Medical Wearables

Abstract Both ecosystems and biological systems in nature have evolved with unique hierarchical branching networks to maximize the efficiency and range of material transmission and adaptability to their external environment. Here we emulate this hierarchical branching (HB) network using a multilayer superposition approach and apply it in the design of flexible pressure sensors for medical wearables. Based on the HB structure, simulation results demonstrate that the deformation of microstructures is efficiently scheduled. Experiments show that the sensitivity of the HB sensor exhibits almost 34- and 55-fold improvements over the medium-pressure and high-pressure ranges, respectively, compared with that of a pressure sensor with a traditional monolayer structure. Successful monitoring of the diverse stimuli from humans demonstrates the considerable potential of the HB sensor in medical wearables. Additionally, the small and thin nature of the sensor enables it to quantify medical diagnostic processes, such as intelligent traditional Chinese medicine pulse diagnosis.