Microstructure-engineered flexible tactile sensors for bioelectronics and human-machine interactions: a review

Flexible tactile sensors, distinguished by their mechanical compliance and skin-like characteristics, have emerged as highly promising platforms for applications in bioelectronics and human-machine interactions. However, their sensing performance remains substantially constrained by intrinsic material limitations, while the persistent trade-off between sensitivity and detection range continues to hinder their practical utility in complex application scenarios. This review systematically summarizes the principal sensing mechanisms of flexible tactile sensors, including capacitive, piezoresistive, piezoelectric, and triboelectric types. Building on this foundation, the review further elucidates the critical role of microstructural engineering in modulating stress distribution and interfacial contact behavior. Furthermore, it highlights recent advances in the applications of flexible tactile sensors in embodied intelligence and bioelectronic monitoring, underscoring their broad application prospects. It further identifies the remaining critical challenges and outlines future research directions in this field. By systematically reviewing recent progress and exploring promising avenues for innovation, this review offers valuable insights to bridge the gap between fundamental research and practical applications. These insights are expected to advance the rational design and development of high-performance flexible tactile sensors enabled by microstructural engineering.