Combinatorial spider-hunting strategy to design multilayer skin-like pressure-stretch sensors with precise dual-signal self-decoupled and smart object recognition ability

Abstract

Bionic electronic skin (e-skin) with intrinsic compressibility and stretchability holds significant potential in robotic haptics, enabling robots to perceive and interact with objects of various shapes effectively. However, creating a biomimetic e-skin with precise dual-signal decoupling remains a challenge. To address this, we present a bifunctional sensor inspired by the spider-hunting mechanism, which captures signals during predation. This sensor is constructed using pressure-stretched multilayer electrospinning of nanofibers-polyvinyl alcohol (CNC-PVA), followed by gas-phase polypyrrole (PPy) polymerization. The innovative superimposed design of the homologous multilayer sensing module, combined with a conductive nanofiber network structure, enables remarkable multi-signal self-decoupling capabilities. Key features of this sensor include high-pressure sensitivity (14.8 kPa ⁻¹ for 0–21 kPa) and an impressively fast response time of 57 ms. As a pressure sensor, it demonstrates repeatability over 5 cycles, while as a stretching sensor, it achieves high sensitivity (gauge factor, GF=1.22) and remains stable over 1000 cycles. Furthermore, this self-decoupled sensing system can independently detect dual signals (shape and weight of objects), thereby empowering robots to recognize and handle various objects more effectively. This multifunctional, low-cost sensor offers an advanced solution to overcome problems in functional e-skin for enhanced robotic object manipulation and recognition capabilities.