A friction identification method in a frequency domain is proposed for a precision servomechanism. A nonlinear friction model including static, Coulomb, and viscous friction as well as Stribeck effect is considered in this paper. Friction models are formulated by using describing functions. Friction elements are estimated through the limit cycle analysis in a velocity control loop. A Butterwort...

The effect of a height-dependent asperity radius of curvature is accounted for in a recently developed scaledependent model of contact and friction. The contact and friction model includes the effects of adhesion, using the Maugis model, and of scale-dependent friction, using the Hurtado and Kim single asperity friction model. This multiasperity model has been modified to include the effect of ...

This paper deals with the formation control of a group of point masses subject to ideal Coulomb friction. We propose a discontinuous controller which provides a solution to the exact formation problem in the presence of ideal Coulomb friction.

This paper deals with the full discretization of quasistatic 3D Signorini problems with local Coulomb friction and a coefficient of friction which may depend on the solution. After a time discretization we obtain a system of static contact problems with Coulomb friction. Each of these problems is solved by the T-FETI domain decomposition method used in auxiliary contact problems with Tresca fri...

We present a new approach to modeling contact between rigid objects that augments an individual Coulomb friction point-contact model with rolling and spinning friction constraints. Starting from the intersection volume, we compute a contact normal from the volume gradient. We compute a contact position from the first moment of the intersection volume, and approximate the extent of the contact p...

This paper analyzes a discrete form of 3D contact problems with local orthotropic Coulomb friction and coefficients of friction which may depend on the solution itself. The analysis is based on the fixed-point reformulation of the original problem. Conditions guaranteeing the existence and uniqueness of discrete solutions are established. Finally, numerical results of a model example are presen...

We use a complementarity approach to pose the Coulomb friction model, combine it with a non-penetration condition, and append to a differential algebraic problem to characterize the dynamics of multibody systems with friction and contact. The resulting problem is relaxed to a Cone Complementarity Problem, whose solution is shown to represent the first order optimality condition of a quadratic p...

This work identifies damping parameters from compliantcontact vibration systems using energy dissipation concept. To develop the identification algorithms, the energy loss as registered in the force-displacement relationship of the real system is balanced against that of a theoretical model incorporating with an idealized compliant contact. Two approaches, including one based on the harmonic re...

Dry friction between hair fibers plays a major role in the collective hair dynamic behavior as it accounts for typical nonsmooth features such as stick-slip instabilities. However, due the challenges posed by the modeling of nonsmooth friction, previous mechanical models for hair either neglect friction or use an approximate smooth friction model, thus losing important visual features. In this ...

In this research work, a 3D numerical modeling technique is proposed based on the 3D particle flow code in order to investigate the failure mechanism of rock foundations. Two series of footings with different geometries and areas are considered in this work. The failure mechanism obtained is similar to that of the Terzaghi’s but there is a negligible difference in between. Lastly, one equation ...