Bioinspired Flexible Tactile Sensor with Hierarchical Microhair Array for Multiscenario Perception

High-precision sensing of interfacial motion has attracted great attention due to its vital role in intelligent microrobotics. However, it is still challenging to develop flexible sensors capable of both multiscenario detection and motion mode identification. Here, we report a flexible magnetic tactile sensor (FMTS) that mimics the hierarchical microsetae of Porthesia similis larvae in nature. When the hierarchical hair array is bent under force, the Hall component detects the tiny changes in the magnetic field due to the rearrangement of internal NdFeB microparticles. The FMTS reaches a maximum sensitivity of 22.02 μT/mN, a high resolution of 0.1 mN, and a linear working range of 0 to 46.26 mN. Diverse multiscenario perceptions are demonstrated, including solid morphology recognition, liquid flow velocity measurement, biological signal monitoring, identification of relative motion mode (e.g., rotation or slippage), and real-time motion monitoring of the grasped objects. This framework advances multiscenario perception in robotic interactions.