Traditional laws of friction believe that the coefficient two specific solids takes a constant value. However, molecular simulations revealed nanosized asperity depends strongly on contact size and radius. Since contacting surfaces are always rough consisting asperities varying dramatically in geometric size, theoretical model is developed to predict behavior fractal this work. The result atomi...

Parts of bears have been used in traditional Chinese medicine for thousands of years in Asia. The use originated in China, and then was adopted by users in Korea and Japan. Today, the use of traditional Chinese medicine is widespread throughout Asia and in Asian communities in North America and Europe. Bear bile from the bear gall bladder is one of the most treasured of traditional Chinese medi...

We present a procedure to perform and interpret pull-off force measurements during the jump-off-contact process between a liquid drop and rough surfaces using a conventional atomic force microscope. In this method, a micrometric liquid mercury drop is attached to an AFM tipless cantilever to measure the force required to pull this drop off a rough surface. We test the method with two surfaces: ...

Mechanical interlocking is widely applied in industry and general lives of human beings. In this work, we realized the control of locking or sliding states of cotton fibers on the metal surfaces with slightly different textures through traditional machining. Three types of sliding states, i.e., locking, one-way sliding, and two-way sliding have been achieved. It is found that the locking or sli...

Suspended graphene sheets exhibit correlated random deformations that can be studied under the framework of rough surfaces with a Hurst (roughness) exponent 0.72 ± 0.01. Here, we show that, independent of the temperature, the iso-height lines at the percolation threshold have a well-defined fractal dimension and are conformally invariant, sharing the same statistical properties as Schramm-Loewn...

Modeling of contact interfaces that inherently include roughness such as joints, clamping devices, and robotic contacts, is very important in many engineering applications. Accurate modeling of such devices requires knowledge of contact parameters such as contact stiffness and contact damping, which are not readily available. In this paper, an experimental method based on contact resonance is d...

We describe a simple method for modeling flexible linear bodies such as ropes and springs, using no dynamic simulation, procedural animation, nor constraint methods—animators create motion by adjusting the shape of models over time using traditional keyframe methods. The approach taken is to provide a default natural rest shape, and to provide controls that perform gross modification and wave-s...

It has long been recognized that surface-laid land mines and other man-made objects tend to have different polarization characteristics than natural materials. This fact has been used to advantage in a number of mine detecting sensors developed over the last two decades. In this work we present the theoretical basis for this polarization dependence. The theory of scattering from randomly rough ...