Reversible Perspiring Artificial Fingertips

Fingertip perspiration is a vital process within human predation, to which the species owes its survival and its biological success. In this paper, the unique human ability of extensive perspiration and controlled friction in self-assembled cholesteric liquid crystals is recreated, mimicking the natural processes that occur in the dermis and epidermis of human skin. This is achieved by inducing porosity in responsive, liquid-bearing material through the controlled-polymerization phase-separation process. The unique topography of human fingerprints is further emulated in the materials by balancing the parallel chirality-induced force and the perpendicular substrate-anchoring force during synthesis. As a result, artificial fingertips are capable of secreting and re-absorbing liquid upon light illumination. By demonstrating the function of the soft material in a tribological aspect, it exhibits a controllable anti-sliding property comparable to human fingertips and subsequently attains a higher degree of biomimicry. This biomimetic fingertip is envisioned being applied in a multitude of fields, ranging from biomedical instruments to interactive, human-like soft robotic devices.

Automated summary

This paper recreates the unique human ability of extensive perspiration and controlled friction in self-assembled cholesteric liquid crystals. It achieves this by inducing porosity in liquid-bearing material through the controlled-polymerization phase-separation process, and emulating the topography of human fingerprints. The biomimetic fingertip exhibits a controllable anti-sliding property comparable to human fingertips and has potential applications in biomedical instruments and soft robotic devices.