The hydrodynamic friction used in many comparisons of isomerization reactions with Kramers’ theory is shown to be related to the translational friction. The fractional viscosity dependence of the translational friction of naphthalene is shown to account for the failure of hydrodynamic models for 1,l ‘-binaphthyl in alkanes. The success of the reorkntational model of friction is also discussed. ...

Friction accounts for more than 60% of the motor torque, and hard nonlinearities due to Coulomb friction and stiction severely degrade control performances as they account for nearly 30% of the industrial robot motor torque. Although many friction compensation methods are available (Armstrong-Helouvry et al., 1994; Lischinsky et al., 1999; Bona & Indri, 2005;), here we only introduce relatively...

nanotechnology involves the ability to see and control individual atoms and molecules which are about 100 nanometer or smaller. one of the major tools used in this field is atomic force microscopy which uses a wealth of techniques to measure the topography and investigates the surface forces in nanoscale. friction force is the representation of the surface interaction between two surfaces an...

This paper presents a dynamic behaviour study of non-linear friction systems subject to uncertain friction laws. The main aspects are the analysis of the stability and the associated non-linear amplitude around the steady-state equilibrium. As friction systems are highly sensitive to the dispersion of friction laws, it is necessary to take into account the uncertainty of the friction coefficien...

This article describes fretting behavior of zirconia and silicon nitride balls on an electro-deposited coating. Fretting tests are performed using a ball-on-flat configuration. The evolution of the kinetic friction coefficient is determined, along with slip ratio. Experimental results show that the steady-state friction coefficient between ceramic balls (Si₃N₄ and ZrO₂) and an electro-deposited...

Analysis and estimation of friction and compensation for its effects in the control of an electrohydraulic manipulator is addressed in this paper. The specific hydraulic manipulator is an integral part of an automated fish processing machine which has been developed in our laboratory. The analysis reveals that considerable static and dynamic friction exists in the system. An available nonlinear...

Solid particles on the floor, both dry and wet, are common but their effects on the friction on the floor were seldom discussed in the literature. In this study, friction measurements were conducted to test the effects of particle size of solid contaminants on the friction coefficient on the floor under footwear, floor, and surface conditions. The results supported the hypothesis that particle ...