Hydrogel-based pressure sensors for electronic skin systems

Abstract

The past few decades have witnessed the rapid development of electronic skin (e-skin) systems in various fields. Among the various sensors integrated into e-skin, pressure sensors are of paramount importance due to their ability to mimic the tactile sensing of human skin. Hydrogels have emerged as ideal materials for fabricating pressure sensors, owing to unique similarities to biological tissues and their versatility and flexibility in tailoring mechanical and electrical properties. This review provides a comprehensive overview of hydrogel-based pressure sensors for e-skin. It begins with summarizing the transduction mechanisms of different types of pressure sensors, followed by a detailed analysis of the classification of conductive hydrogels. Additionally, various structure design strategies aimed at enhancing sensing performance are summarized. Subsequently, promising applications, such as healthcare monitoring, tactile recognition, and human-machine interactions, are highlighted. Finally, the challenges and prospects of sensors are discussed, aiming to inspire further innovations in this captivating area of research.