Robust self-cleaning and micromanipulation capabilities of gecko spatulae and their bio-mimics

Abstract

Geckos have the extraordinary ability to prevent their sticky feet from fouling while running on dusty walls and ceilings. Understanding gecko adhesion and self-cleaning mechanisms is essential for elucidating animal behaviours and rationally designing gecko-inspired devices. Here we report a unique self-cleaning mechanism possessed by the nano-pads of gecko spatulae. The difference between the velocity-dependent particle-wall adhesion and the velocity-independent spatula-particle dynamic response leads to a robust self-cleaning capability, allowing geckos to efficiently dislodge dirt during their locomotion. Emulating this natural design, we fabricate artificial spatulae and micromanipulators that show similar effects, and that provide a new way to manipulate micro-objects. By simply tuning the pull-off velocity, our gecko-inspired micromanipulators, made of synthetic microfibers with graphene-decorated micro-pads, can easily pick up, transport, and drop-off microparticles for precise assembling. This work should open the door to the development of novel self-cleaning adhesives, smart surfaces, microelectromechanical systems, biomedical devices, and more.

Effect of Hydrogen Concentration on the Growth of Carbon Nanotube Arrays for Gecko-Inspired Adhesive Applications

“…This unique adhesive capability of geckos has led to the development of advanced adhesives, including dry adhesives, which unlike chemical adhesives, leave no residue [3]. Such dry adhesives generally have micro-nano array structures, and are expected to be suitable for robotic end-effectors [4][5][6][7]. At present, there are generally two main types of materials being researched as materials for gecko-inspired dry adhesives [8]: Synthetic polymers [5,9,10] and vertically-aligned carbon nanotubes (VACNTs) [11][12][13][14].…”

Imparting amphiphobicity on single-crystalline porous materials

“…The custom design of surfaces with controlled wettability properties has been attracting continuous attention from both academia and industry1234567. In particular, amphiphobic surfaces89101112 that repel water and compounds with low surface tension (for example, oils) are of great interest due to their various prospective applications, such as oil transportation13, microfluidics14 and nano-object manipulation15.…”

Enhanced Locomotion Efficiency of a Bio-inspired Walking Robot using Contact Surfaces with Frictional Anisotropy

“…These attachment devices can provide optimal friction for forward motion, protect animals from slipping on a surface, and even allow them grip surfaces firmly. From this point of view, several works have investigated biological materials678910 and used them as an inspiration to develop materials1112 for robotic applications1314151617.…”