Strain-Insensitive, Crosstalk-Suppressed, Ultrawide-Linearity Iontronic Tactile Skin from a Synergistic Segment-Embedded Strategy

Tactile sensing arrays play a crucial role in human-machine interaction, robotics, and artificial intelligence by enabling the perception of physical stimuli on robotic surfaces or human skin. However, skin-attachable sensor arrays still suffer from strain interference and signal crosstalk under stretching or bending, particularly on curved or deformable surfaces. Here, we present a stretchable tactile array that is both strain-insensitive and crosstalk-suppressed, achieved via a hierarchically segmented design that mitigates lateral and vertical deformations synergistically. By tessellating hard and compliant elements within encapsulation layers, stretch deformation in the sensing region is reduced by 79%, and the overall mean stress is decreased by over 90%. Multilevel segmented spacers are proposed to provide vertical support while maintaining stretchability. These synergistic designs achieve comprehensive strain insensitivity (75% stretching insensitivity and bending insensitivity) and ultralow crosstalk (31.82 dB). Furthermore, iontronic porous foams are introduced to endow sensing pixels with high linearity (R2 = 0.985) and sensitivity (2.812 kPa-1). We demonstrate accurate tactile information acquisition on soft, curved human fingers and showcase the array's potential for multi-attribute object recognition.