Direct tyre-road contact friction estimation is essential for future active safety systems. Friction estimation methods were proposed earlier for driving conditions in the presence of a slip angle or slip ratio. However, the estimation of friction from a freely rolling tyre is still an unsolved topic. This study uses three 3-axis accelerometers on the inner liner of a tyre to detect friction po...

Using frictional force microscopy (FFM), the friction surface characteristics were compared between twisted nematic (TN) mode and vertical alignment (VA) mode alignment films (AFs). The friction asymmetry was detected depending on temperature conditions on TN mode AF, but not on VA mode AF. The difference between two modes was explained by leaning intermolecular repulsion caused by the pre-tilt...

A conventional description of the effect of meniscus friction is based on the concept of the dynamic contact angle u, which depends on the meniscus velocity V according to the Tanner law, u}V. However, recent high-resolution experiments on spontaneous uptake of wetting fluids by capillaries have questioned the universality of the Tanner law. We analyze a mechanism underlying the phenomenologica...

PURPOSE About 70% injury of gymnasts happened during landing - an interaction between gymnast and landing mat. The most injured joint is the ankle. The current study examined the effect of mechanical properties of landing mat on ankle loading with aims to identify means of decreasing the risk of ankle injury. METHOD Gymnastic skill - salto backward stretched with 3/2 twist was captured by two...

Friction stir welding (FSW) is a promising technique to join aluminum alloys without having problems encountered during fusion welding processes. In the present work, the evolution of microstructure and texture in friction stir welded thin AA2024 aluminum alloy are examined by electron backscattered diffraction (EBSD) technique. The sheets with 0.8 mm thickness were successfully welded by frict...

the previous studies show that a high percentage of traffic accidents take place in two-lane rural highways and most of which happen at horizontal curves. meanwhile the horizontal alignment is often subject to hard topographic conditions where because of economic aspects designers are forced to design horizontal curves at grades. vertical angle of longitudinal slope reduces the normal force of ...

nowadays the surface texturing has been widely recognized as a usable capability to improve the tribological systems. in this paper, ultrasonic assisted turning (uat) isperformed to create the micro textures on the flat faces. micro surface texturing ismade on the al7075-t6 by the uat in the face turning process. then, the influences of cutting speed feed, vibration direction and vibration ampl...

The linear viscoelastic behaviors of single semiflexible chains with internal friction are studied based on the wormlike-chain model. It is shown that the frequency dependence of the complex compliance in the high frequency limit is the same as that of the Voigt model. This asymptotic behavior appears also for the Rouse model with internal friction. We derive the characteristic times for both t...