Multilevel Cu-LIG Tactile Sensing Arrays for 3D Touch Human–Machine Interaction

High-performance flexible tactile sensors have attracted significant attention in the domains of human–machine interactions. However, the efficient fabrication of sensors with highly sensitive responses over a broad load range still remains a challenge. Here, we propose a one-step laser writing route to construct a distinctive multilevel piezoresistive structure, consisting of Cu nanoparticle-doped graphene protrusions and surrounding porous Cu sheets. This multilevel structure enables the assembled tactile sensors to exhibit superior sensitivity at both low-pressure (1468 kPa^–1 at 0–200 kPa) and high-pressure (1345 kPa^–1 at 600–800 kPa) stimulations. Its enhancement mechanism for piezoresistive sensing has been investigated. The programmable laser writing process facilitates the development of human–machine interaction devices that recognize multidimensional gestures such as sliding, clicking, and pressing. This advancement serves to promote the development of high-performance interactive sensing technologies.