Aiming at the inspection of rough stone and concrete wall surfaces, a grasping module of cross-arranged claw is designed. It can attach onto rough wall surfaces by hooking or grasping walls. First, based on the interaction mechanism of hooks and rough wall surfaces, the hook structures in claw tips are developed. Then, the size of the hook tip is calculated and the failure mode is analyzed. The...

Surface roughness is known to easily suppress the adhesion of elastic surfaces. Here, a simple model for the contact of viscoelastic rough surfaces with significant levels of adhesion is presented. This approach is derived from our previous model (Barthel, E.; Haiat, G. Langmuir 2002, 18, 9362) for the adhesive contact of viscoelastic spheres. For simplicity, a simple loading/unloading history ...

We study the adhesion between smooth polydimethylsiloxane (PDMS) rubber balls and smooth and rough poly(methyl methacrylate) (PMMA) surfaces, and between smooth silicon nitride balls and smooth PDMS surfaces. From the measured viscoelastic modulus of the PDMS rubber we calculate the viscoelastic contribution to the crack-opening propagation energy γeff(v,T) for a wide range of crack tip velocit...

We describe the surface properties of a simple lattice model of a sandpile that includes evolving structural disorder. We present a dynamical scaling hypothesis for generic sandpile automata and, additionally, explore the kinetic roughening of the sandpile surface, indicating its relationship with the sandpile evolution. Finally, we comment on the surprisingly good agreement found between this ...

By means of the extinction-theorem method, previously reported by J. M. Soto-Crespo and M. Nieto-Vesperinas [J. Opt. Soc. Am. A 6, 367 (1989)], the intensity statistics of the s-polarized electromagnetic field scattered from randomly rough, perfectly conducting, one-dimensional surfaces are studied in the case of surface transverse correlation lengths larger than the wavelength. In particular, ...

OBJECTIVE To systematically collect and evaluate existing evidence on the effects of different mechanical instruments on the surface characteristics of smooth and rough titanium surfaces. MATERIALS AND METHODS PubMed-MEDLINE, Cochrane-CENTRAL and EMBASE databases were searched up to December 2010 to identify appropriate studies. The eligible studies were controlled studies investigating titan...

one of the most important factors that affect tire friction is surface roughness, which determines the size of the real contact area, real pressure distribution on the contact interface, and scales of mechanical engagement between viscoelastic rubber and a rough substrate. the need to predict coefficient of friction (cof) for rubber on rough surfaces for applications such as traction of tires o...

Implicit surface techniques provide useful tools for modeling and rendering smooth surfaces. Deriving implicit formulations for fractal representations extends the scope of implicit surface techniques to rough surfaces. Linear fractals modeled by recurrent iterated function systems may be de ned implicitly using either geometric distance or escape time. Random fractals modeled using Perlin's no...

geometrical profile (roughness) of joint surfaces influences the behaviour of rock joints under shear loading. with regard to the dilation, there are two models of direct shear test that may simulate the original loading condition existing in the location from where the specimens have been sampled. the first model in which the normal load is constant (cnl) and the discontinuity is free to dilat...

Implicit surface techniques provide useful tools for modeling and rendering smooth surfaces. Deriving implicit formulations for fractal representations extends the scope of implicit surface techniques to rough surfaces. Linear fractals modeled by recurrent iterated function systems may be deened implicitly using either geometric distance or escape time. Random fractals modeled using Perlin's no...