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 [1]. By assuming a contact patch between the tire and the ground we develop a partial differential equation for the distribution of the fr...

We show that the static friction force which must be overcome to render a sticking contact sliding is reduced if an external torque is also exerted. As a test system we study a planar disk lying on a horizontal flat surface. We perform experiments and compare with analytical results to find that the coupling between static friction force and torque is nontrivial: It is not determined by the Cou...

We review the state of the art in friction estimation and rendering for haptic interfaces and present a method based on a modified Karnopp friction model. We illustrate some of the advantages of this approach and show how it can be used to create accurate and convincing displays of sliding friction, including pre-sliding displacement and stick-slip behavior. We also present the results of human...

Experimental studies were conducted on an off-highway heavy duty diesel engine running on different viscosity grade engine oil, for determining the friction power in a firing engine by measuring the indicated mean effective pressure (IMEP) by in–cylinder pressure sensor and calculating the Indicated power and Brake power. It is known fact that hydrodynamic friction is related to the viscosity o...

Direct tire-road contact friction estimation is essential for future autonomous cars and active safety systems. Friction estimation methods have been proposed earlier for driving conditions in the presence of a slip angle or slip ratio. However, the estimation of the friction from a freely-rolling tire is still an unsolved topic. Knowing the existing friction potential would be beneficial since...

recent developments in nanostructured products draw considerable attention to ultrafine grained materials. these materials are normally manufactured by different severe plastic deformation (spd) methods. in the present study, analytical models and finite element method (fem) are used to calculate strain imposed to a specimen that was deformed by equal channel angular pressing (ecap). in additio...

introduction: any decrease in friction between orthodontic wire and bracket can accelerate tooth movement in the sliding technique and result in better control of anchorage. the present study was carried out to decrease this friction by coating of zinc oxide nanoparticles (zno) on orthodontic wires and porcelain brackets. materials and methods: in this in vitro study, a combination of 120 0.019...

basic processes (e.g., phonon generation and electron–hole pair creation); thus, determining energy dissipation mechanisms offers the potential to control friction in new ways. [ 3–5 ] Theoretically, when an object is moving along an insulator surface, kinetic energy is dissipated solely through phonon emission (i.e., lattice vibration of the substrate). However, if the substrate is conductive,...

For control applications aiming accurate positioning and path tracking friction modelling and compensation can be very important, especially when working with small displacements as usual in nano technologies. The paper at hand describes friction identification and friction model application for a linear high-precision ball bearing guide driven by a voice coil actuator and using high-resolution...

Tribology-the science of friction, wear and lubrication-is of great importance for all technical applications where moving bodies are in contact. Nonetheless, little progress has been made in finding an exact atomistic description of friction since Amontons proposed his empirical macroscopic laws over three centuries ago. The advent of new experimental tools such as the friction force microscop...