Controlling and predicting friction is a significant scientific technological issue. It our everyday experience that two smooth surfaces slide more easily over each other than rough ones, due to interlocking of the surfaces. However, interpretation such forces difficult since contributions arise from e.g. adhesion forces, are harder control. Here, we demonstrate designer macroscopic roughness c...

The physics of motion of a sliding object can be used to plan sensorless robot manipulation strategies based on sliding. Prediction of a sliding object's motion is difficult because the object's distribution of support on the surface, and the resulting frictional forces, are in general unknown. We describe a new approach to the analysis of sliding motion, which finds the set of object motions f...

Control and reduction of friction is one of the last frontier in the field of tribology. This paper presents a model for low friction made up of a self-excited oscillator sliding along a periodic potential. Many examples of such self-excited oscillators in electrical, mechanical and biological systems can be found in literature. As one of its most prominent features, stable limit cycles in phas...

Investigation of the stationary load-deflection behaviour of tyres reveals many details of the structure and the rubber to road friction properties. These characteristics are fundamental to the understanding of the behaviour of both the stationary and the rolling tyre. In connection with racing, tyre static stiffness characteristics are of interest as they reflect on the controllability of the ...

Diamond and diamondlike carbon (DLC) films exhibit a wide range of sometimes contradictory tribological behavior. Experimentally, isolating the influences of factors such as film structure, testing conditions, and environmental effects has proven difficult. In this work, molecular dynamics simulations were used to examine the effects of film structure, passivation, adhesion, tribochemistry, and...

We study the lubricated (wet) contact mechanics of a smooth hard cylinder sliding on a randomly rough nominally flat surface of a linear viscoelastic solid. We calculate the rolling and sliding friction, and study the transition from the boundary lubrication to the elasto-hydrodynamic lubrication regime. For the viscoelastic contact the minimum (average) separation does not monotonically increa...

friction stir processing was applied for fabricating an aluminum alloy based hybrid nano composite reinforced with nano sized al2o3 and micro sized graphite particles. a mixture of al2o3 and graphite particles was packed into a groove with 1 mm width and 4.5 mm depth, which had been cut in 5083 aluminum plate of 10 mm thick. packed groove was subjected to friction stir processing in order to im...