Tactile sensing in intelligent robots: from bionic structures to fabrication and applications

The integration of flexible sensors with bionics has brought about a revolutionary change in intelligent robots, enabling biological-level tactile interactions between the physical and digital worlds. Among these, the high sensitivity, high resolution, fast response, and multi-modal perception capabilities of tactile sensors provide an important basis for robot perception. There are still some issues in terms of structural and functional balance, realization of microscale manufacturing, and practical adaptation. This article reviews the inspiration sources and sensitive material selection for bionic tactile sensors, focusing on the hierarchical biomimetic mechanism at different scales from micro to macro. Subsequently, it summarizes the micro/nano manufacturing processes for the preparation of flexible tactile sensors, namely, additive manufacturing, laser induction, template-induced growth, and transfer printing technologies. Additionally, the emerging applications of flexible tactile sensing in the field of embodied intelligence, including intelligent wearables, flexible grasping, and robot interaction, are introduced. Finally, we discuss future directions from the perspectives of neuromorphic bionics and intelligent manufacturing, and these technologies are expected to establish a new paradigm for embodied intelligent tactile sensing. This work combines theoretical mechanisms with practical progress, opening up new opportunities in this rapidly developing field.