High‐Fidelity Fabrication of 3D Multiscale‐Structured Pressure Sensors for High‐Performance Wearable Sensing

ABSTRACT Constructing multiscale structures has been regarded as a promising strategy to improve the overall performance of flexible pressure sensors. However, their manufacturing approach remains a challenge due to the lack of mild, compatible, and scalable processing methods. In this work, a high‐precision and controllable fabrication strategy based on a novel secondary replica molding approach is proposed. A paraffin intermediate mold is introduced to reduce potential damage to functional sensing materials, which enables the precise construction of arbitrary structures. The resulting multiscale‐structured octet‐truss piezoresistive pressure sensor (MSPS‐O) exhibits exceptional batch‐to‐batch reproducibility with a deviation of volume‐normalized initial resistance <2.5%. Notably, the sensor delivers a favorable balance between sensitivity and detection range, demonstrating a high sensitivity of 0.219 kPa −1 and a wide detection range of up to 809 kPa. It also exhibits remarkable long‐term cyclic stability over 15 000 loading cycles with less than 4% deviation. Furthermore, MSPS‐O can be utilized for real‐time monitoring of human motion, and can accurately distinguish different gait patterns through machine learning algorithms. This work offers a new approach for the reliable manufacturing technology of multiscale‐structured flexible sensors with high stability and consistency.