Meeting Abstract
It has been nearly 20 years since Autumn and colleagues established the central role of van der Waals forces in how geckos stick. Much has been discovered about the structure and function of fibrillar adhesives in geckos and other taxa, and substantial success has been achieved in translating natural models into bioinspired synthetic adhesives. Nevertheless, synthetics still cannot match the multidimensional performance observed in the gecko system that is simultaneously robust to dirt and water, resilient over thousands of cycles, and competent on surfaces that are rough at drastically different length scales. Apparent insensitivity of adhesion to variability in roughness is particularly interesting from both a theoretical and applied perspective. Progress on understanding the extent to which and the basis of how the gecko system is robust to roughness is impeded by complexity of quantifying roughness of natural surfaces and a dearth of data on gecko substrate use. We review methods for characterizing rough surfaces as they relate to the potential for collecting relevant estimates of variation in gecko adhesive performance across different substrates in their natural habitats. Our goal is to suggest tractable and practical protocols to enable researchers to design detailed studies of structure-function relationships of the gecko fibrillar system that translate into its ability to deliver robust adhesion across large variation in roughness. Such data can help advance development of design parameters to improve bioinspired adhesives based on the gecko fibrillar system.
