In this work, the plane-on-plane torsional fretting tribological behavior of polytetrafluoroethylene (PTFE) was studied. A model of a rigid, flat-ended punch acting on an elastic half-space was built according to the experimental conditions. The results indicate that the shape of T-θ curves was influenced by both the torsional angle and the normal load. The torsion friction torque and wear rate...

This paper introduces a method of design and implementation of a two-wheeled inverted pendulum (TWIP) robot with friction compensation. Friction in the drive mechanism is a critical factor of robot self-balancing and affects its performance. The friction parameters are identified based on the dynamic model of the drive mechanism. The dynamics of the whole robot system are obtained by the Lagran...

In this paper, we investigate the friction behaviors of graphene flakes sliding on a gold substrate using molecular dynamics simulations. The effects of flake size, flake shape, relative rotation angle between flake and substrate, and crystal orientation of substrate on the friction process are thoroughly studied. It is found that under the same load, the average friction forces per atom are sm...

We present particulate simulation results for translational and rotational friction components of a shish-kebab model of a colloidal rod with aspect ratio (length over diameter) L/D=10 in the presence of a planar hard wall. Hydrodynamic interactions between rod and wall cause an overall enhancement of the friction tensor components. We find that the friction enhancements to reasonable approxima...

Original scientific paper In this paper, the orthogonal cutting force model is proposed comprising forces due to flank wear in addition to the forces for chip formation during the hard turning of round bar made of steel 60WCrV7 hardened at 55+2HRc. Cutting force model includes two tool conditions: perfectly sharp tool with VBB = 0 and tool with maximum permissible flank wear VBBmax. Based on cu...

A calibration process is developed to determine the parameter values. Three-axial compressions tests in laboratory and neural network are used to determine the material internal friction angle and stiffness, respectively. These tests are repeated numerically using PFC models with different sets of particle friction coefficients and particle stiffness values. Three-axial compressions tests are f...

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...

slope stability analysis is an enduring research topic in the engineering and academic sectors. accurate prediction of the factor of safety (fos) of slopes, their stability, and their performance is not an easy task. in this work, the adaptive neuro-fuzzy inference system (anfis) was utilized to build an estimation model for the prediction of fos. three anfis models were implemented including g...