Theoretical and Experimental Study of a Novel Microfabricated Fibrillar Structure

Abstract

Survival of species such as geckos, spiders, flies, and crickets crucially depends on the interaction between hundreds of thousands of hairs or setae on their feet. Recently, many efforts have been made to fabricate adhesive pads inspired by natural biological systems. Fibres developed from nano molding can mimic the hairs of these species' feet and act as a dry adhesive pad. In this study, for the nanocasting of nano fibres, several porous silicon structures with desired dimensional and morphological characteristics were made by an electrochemical etching system. The adhesive strengths of produced adhesive pads were measured about 0.07 N/cm 2 in the normal direction and about 0.045 N/cm 2 in the shear direction in contact with a glass surface. Besides the experimental work, a quantitative model has been developed to model van der Waals interactions in adhesive pads. The results from the theoretical model show consistency with experiments.