The initial microstructure plays an important role in determining the spatial and temporal evolution of the microstructure during friction stir welding (FSW). The overall kinetics of microstructural evolution is location sensitive and the effect of the process strain, strain rate and thermal cycle creates complexities. In the present study, magnesium based WE43 alloy has been welded employing t...

Application of thermoplastic materials has increased dramatically in recent decades due to its recyclability, low density, resistance to chemical changes. The friction stir welding process is one of the new methods of solid state welding, which has recently undergone a significant improvement. In this research, using a new tool Made of plain carbon steel st37 in friction stir welding and low co...

This paper presents a realistic dynamic simulation of the closed-loop tip motion of a rigid-link manipulator with joint friction. The results from two simulation techniques are compared with experimental results. A six-axis industrial Stäubli robot is modelled. The LuGre friction model is used to account both for the sliding and pre-sliding regime. The manipulation task implies transferring a l...

Physical therapists are trained in manual examination techniques to test the impaired motor functions of patients. In this study, we have introduced a wearable robotic dummy joint to simulate disordered joint resistances or behaviors to support physical therapists in learning such techniques. We developed a discontinuous joint friction model based on a stick-slip phenomenon to simulate knee joi...

important functions: joint lubrication, stress distribution to subchondral bone to minimize peak stress, and provision of a smooth low-friction surface. Repetitive and acute impact, as well as torsional joint loading can damage articular cartilage surfaces of the knee joint. Injury to articular cartilage can lead to pain, swelling, joint dysfunction, and possibly progressive joint degeneration....

Abstract Studying the lubrication properties of osteoarthritis (OA) synovial fluid (SF) enables an understanding boundary joint, mobility, and friction. However, tribology has never been combined with clinical reality presence worn particles within how they affect osteoarthritic joints. Part problem relates to methods studying friction by applying inadequate pin-on-disc techniques. In this stud...

Friction stir welding is a relatively new solid state joining process, which is suitable for welding similar and dissimilar materials.  The present research work concentrates on the effect of tool rotational speed on the tensile, microstructural properties and microhardness of the friction stir welded joints of different grades of austenitic stainless steel sheets. Four different tool rotationa...

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...