High precision applications, such as, semiconductor manufacturing and diamond turning of optical elements require positioning accuracy within nanometers and therefore require very precise motion control of machine tool axes. The frictional behavior at the slides is a result of very complex interaction between the contacting surfaces and lubricants. No accurate quantitative prediction of the fri...

We present novel results on flow properties using molecular dynamics simulation as well as γ -densitometry experiments. We show that fundamentally different types of granular flow can be observed in one unique system. Using both frictional and frictionless confining walls, we show that the differences existing between these regimes originate in the frictional properties of the walls. The salien...

Energy savings by reducing the thermal and mechanical losses in machines is of major concern due to continuous depletion of energy resources. Frictional losses of engine components cause energy losses leading to high fuel consumption. In piston assembly, piston skirt and liner interaction contribute as much as a frictional loss as the piston rings but more studies have been focused on piston ri...

The nonlinear frictional behavior of two-dimensional (2-D) and three-dimensional (3-D) models are compared in this study of fides in the Bight of Abaco. The shallow depths and the existence of an extensive set of tidal elevation data (five astronomical and two overtide constituents at 25 stations) from Filloux and Snyder (1979) offer an excellent opportunity to compare the effects of different ...

There are several applications in robotics and manufacturing in which nominally rigid objects are subject to multiple frictional contacts with other objects. In most previous work, rigid body models have been used to analyze such systems. There are two fundamental problems with such an approach. Firstly, the use of frictional laws, such as Coulomb's law, introduce inconsistencies and ambiguitie...

Synovial fluid plays an important role in lubricating synovial joints. Its main constituents are hyaluronic acid (HA) and γ-globulin, acting as boundary lubricants for articular cartilage. The aim of the study was to demonstrate the concentration-dependent effect of HA and γ-globulin on the boundary-lubricating ability of human osteoarthritis (OA) cartilage. Normal, early and advance stage arti...

The scan-velocity dependence of friction force microscopy (FFM) is characterized on gelatin films and related to the rate dependence of molecular relaxations. For selected scanning-parameter values the velocity dependence of frictional force is affected by the measurement process, because of energy imparted to the tip-sample contact region: a peak in the friction-velocity relationship, attribut...

The microstructure investigated in this study was inspired by the anisotropic microornamentation of scales from the ventral body side of the California King Snake (Lampropeltis getula californiae). Frictional properties of snake-inspired microstructured polymer surface (SIMPS) made of epoxy resin were characterised in contact with a smooth glass ball by a microtribometer in two perpendicular di...

Frictional vibration and noise caused by water-lubricated rubber stern tube bearings, which are generated under extreme conditions, severely threaten underwater vehicles' survivability and concealment performance. This study investigates the effect of flaky and spherical MoS2 nanoparticles on tribological properties and damping capacity of water-lubricated rubber materials, with the aim of decr...

The frictional forces between the sports footwear and the ground can induce distorsion trauma to the lower extremity. Two cases are reported in which fractures about the ankle are related to this friction. An adjustment and reduction of the frictional forces are recommendable.