A review of adhesion and friction models for gecko feet

Abstract

The attachment pads of geckos exhibit the most versatile and effective adhesive known in nature. Their fibrillar structure is the primary source of high adhesion and their hierarchical structure produces the adhesion enhancement by giving the gecko the adaptability to create a large real area of contact with surfaces. Although geckos are capable of producing large adhesive forces, they retain the ability to remove their feet from an attachment surface at will. Detachment is achieved by a peeling motion of the gecko's feet from a surface. During the last few years, many researches have been conducted to develop the theoretical models that explain the gecko to adhere and detach from surfaces at will, including micro/macroscopic gecko adhesion, friction and peeling models for gecko hierarchical fibrillar structure contacting to rough surface. This review describes the progress in the modeling filed for gecko adhesion, friction and peeling, and discussed the future issues for gecko modeling. © KSPE and Springer 2010.