In this paper we derive a new dynamic friction force model for the longitudinal road/tire interaction for wheeled ground vehicles. The model is based on a dynamic friction model developed previously for contact-point friction problems, called the LuGre model [7]. By assuming a contact patch between the tire and the ground we develop a partial differential equation for the distribution of the fr...

The motion of a uid subject to Navier{Stokes equations with Coriolis force, to a Robin type traction condition at the surface and to a friction condition at the bottom is investigated. An asymptotic model is derived as the aspect ratio = depth/width of the domain go to 0. When Reynolds number is not too large, this is mathematically justiied and the 3D limit velocity is given in terms of wind, ...

"Walking-Mode Maps", based on Slip/Non-Slip criteria, are proposed. Slip/Non-Slip criteria are expressed as follows: for a slip to occur: |F(h)/F(n)|(h) > or = mu(s) or |F(h)/F(n)|(t) > or = mu(s); for no slip to occur: |F(h)/F(n)|(h) < mu(s) or |F(h)/F(n)|(t) < mu(s). |F(h)/F(n)|(h) and |F(h)/F(n)|(t) are the maximum peak value of the traction coefficient at heel-strike and toe-off respectivel...

Abstract—In this work, effects of the friction and truncation on the dynamics of a double-cone gravitational motor, self-propelled on a straight V-shaped horizontal rail, are evaluated. Such mechanism has a variable radius of contact, and, on one hand, it is similar to a pulley mechanism that changes the potential energy into the kinetic energy of rotation, but on the other hand, it is similar ...

Intergranular pressure solution creep is an important deformation mechanism in the Earth's crust. The phenomenon has been frequently studied and several analytical models have been proposed that describe its constitutive behavior. These models require assumptions regarding the geometry of the aggregate and the grain size distribution in order to solve for the contact stresses and often neglect ...

Cell adhesion is regulated by the mechanical characteristics of the cell environment. The influences of different parameters of the adhesive substrates are convoluted in the cell response leading to questions on the underlying mechanisms, like biochemical signaling on the level of adhesion molecules, or viscoelastic properties of substrates and cell. By a time-resolved analysis of traction forc...

The purpose of the present study was to determine the loads acting on the lumbar spine when traction therapy was given in the Fowler's position. The study had two parts: a theoretical analysis which showed that traction produced a flexion moment on the spine as well as axial distraction; and an experimental study which measured the flexion moment induced by the adoption of the Fowler's position...

Hip arthroscopy is being used with increasing frequency as the understanding of arthroscopic management of groin pain improves. To access the hip joint arthroscopically, traction must be placed on the leg. In most cases, countertraction is provided with a padded post in the groin. Complications of traction are often attributed to the post and include perineal or pudendal neuropraxias and skin c...

With the uncertainty regarding global energy future, ability to lubricate concentrated contacts with sufficiently thick liquid films while minimizing friction is of extreme importance. The assumptions classical elastohydrodynamic lubrication have remained unchanged since early days. It has not been possible test many these without measurement viscosity at (EHL) pressures, and viscometer measure...