The research objective of this grant is to elucidate contact self-cleaning mechanics of natural and synthetic micro/nano-fibrillar adhesive materials and design and demonstrate high performance synthetic elastomer fibrillar adhesives with such self-cleaning capability. Geckos and beetles can clean their foot-hairs when they are contaminated with particulates on surfaces by several cycles of loading, shearing, and unloading of their footpads on a clean surface, called contact self-cleaning. Such biological self-cleaning mechanics of is not fully understood yet. Moreover, although the recent synthetic fibrillar adhesives have demonstrated high strength and repeatability as good as biological counterparts on clean and smooth surfaces, their performance degrades significantly on dirty surfaces since they cannot shed the dirt particles. To achieve the research objectives of this project, the research tasks include modeling of self-cleaning mechanics of fibrillar adhesives, development of a design method for high performance elastomer fibrillar adhesives with such self-cleaning capability, and fabrication and characterization of directional elastomer fiber arrays.
The proposed bio-inspired fibrillar gripping materials with contact self-cleaning capability would enable new commercial gripping materials that could work repeatedly and reliably in broad real-world commercial applications such as sports, flexible electronics, medicine, space, product design, packaging, and robotics. Interdisciplinary research work in this study will be transferred to many educational activities in mechanical engineering, robotics, and bioengineering. Two new courses developed by the principle investigator will use the biologically inspired adhesive and micro-mechanics concepts and research facilities and results in this project to design and implement new bio-inspired materials in student semester-long projects.