3D printing wide detection range and high sensitivity flexible pressure sensor and its applications

Piezoresistive flexible pressure sensors hold significant promise in various applications, including electronic skin, human-machine interaction, and health monitoring. Nevertheless, conventional piezoresistive flexible pressure sensors encounter challenges in achieving both high sensitivity and wide detection range, which remain unresolved. The design of a sensor's microstructure presents itself as an effective strategy for enhancing sensor performance. Microporous structure is a commonly employed microstructure that substantially enhances the sensor's detection range. However, flexible pressure sensors with microporous structures often exhibit low sensitivity which limits their applications. Consequently, this study introduces an innovative layered and microporous structure to upgrade flexible pressure sensor with high sensitivity as well as wide detection range. By integrating 3D direct writing printing technology with foaming materials, multi-walled carbon nanotubes are incorporated as conductive fillers to fabricate a piezoresistive flexible pressure sensor (PPS) featuring both microporous and 3D structures. This sensor exhibits high sensitivity (0.298 kPa−1), a wide detection range (25 Pa to 130 kPa), favorable response time, and durability, which can be applicable to robotic arms, smart gloves, and other devices requiring effective stress detection. This study unveils novel design concepts for a category of piezoresistive flexible pressure sensors that are compatible with high sensitivity and wide detection range requirements.