Interfacial propulsion by directional adhesion

Interfacial propulsion by directional adhesion

The rough integument of water-walking arthropods is well known to be responsible for their water-repellency [1, 2, 3, 4]; however, water-repellent surfaces generally experience reduced traction at an air-water interface [5, 6, 7, 8]. A conundrum then arises as to how such creatures generate significant propulsive forces while retaining their water-repellency. We here demonstrate through a serie...

Interfacial adhesion of graphene by multiscale models

This article presents a multiscale study on adhesive interactions between graphene and its substrates. First, van der Waals (vdW) interactions between graphene and a SiO2 substrate are studied by fi rst-principle density functional theory (DFT) calculations with dispersion corrections. It is found that the interaction strength is strongly infl uenced by changes of the SiO2 surface structures du...

Harnessing bistability for directional propulsion of untethered, soft robots

In most macro-scale robotics systems , propulsion and controls are enabled through a physical tether or complex on-board electronics and batteries. A tether simplifies the design process but limits the range of motion of the robot, while on-board controls and power supplies are heavy and complicate the design process. Here we present a simple design principle for an untethered, entirely soft, s...

Improving Interfacial Adhesion in Pla/wood Biocomposites

Effect of Interfacial Slippage on Viscoelastic Adhesion

Peeling of a viscoelastic adhesive from a solid substrate poses a wonderful problem of polymer flow. When the adhesive is peeled, it is also stretched in a direction normal to the substrate. The concomitant Poisson contraction creates a pressure gradient and thus induces a shear flow in the adhesive close to the delamination front. Earlier it was pointed out that the strength of viscoelastic ad...