609d Towards Understanding the Gecko Adhesive and Related Biomimetic Systems

Hongbo Zeng1, Jacob N. Israelachvili1, and Matthew Tirrell2. (1) Chemical Engineering, University of California at Santa Barbara, 3357 Engineering II, Santa Barbara, CA 93106-5080, (2) Chemical Engineering, University of California, Santa Barbara, 3357 Engineering II, Santa Barbara, CA 93106-5080

Geckos have extraordinary climbing abilities, and they can attach and easily detach from almost any kind of surface. Understanding the mechanism behind the gecko adhesive system has received a lot of experimental and theoretical attention recently because of the significant potential of creating bio-inspired synthetic dry adhesives and robots. The high adhesion and friction of gecko feet are mainly attributed to van der Waals and friction forces which are coupled via the complex hierarchical structure of the toes with their characteristic dimensions and geometries. This talk will mainly discuss: (1) theoretical analysis and modeling of the quick attachment and detachment of gecko feet based on a tape mode, demonstrating the role of the geometry in the enhancement of the adhesion and coupled friction; and (2) analysis of the adhesion and friction of bio-inspired patterned surfaces. Our results, when considered with recent experiments, suggest criteria for simultaneously optimizing the adhesion and friction of bio-inspired patterned surfaces.