Modelling and identification of flexible-joint robots is required for dynamic simulation and model based control of industrial robots. A nonlinear finite element based method is used to derive the dynamic equations of motion in a form suitable for both simulation and identification. The latter requires that the equations of motion are linear in the dynamic parameters. For accurate simulations o...

N. Ratković, Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia. R. Nikolić, Faculty of Civil Engineering, University of Žilina, Žilina, Slovakia. I. Samardžić, University of Osijek, Mechanical Engineering Faculty in Slavonski Brod, Croatia. Fundamental principles of friction welding of dissimilar steels (high speed and tempering steel) from the aspect of metallurgical and che...

It is a research which could enter into contradiction with the current trend concerning the hip implants. It is known as sliding friction, which is characteristic of present artificial hip joints, is higher than in the case of rolling friction. The paper reports the studies of the functioning mode of a novel spherical bearing MoM (metal on metal) with rolling friction, with potential applicatio...

Joint friction is a major problem in accurate robot position control, particularly during low-speed, small-amplitude tasks. This paper proposes a simple, practical, and e!ective method to compensate for joint friction, using a six-axis force/torque sensor mounted under the manipulator. From these measurements, joint torques are estimated and used in a torque controller, which virtually eliminat...

The diarthrodial, knee joint is a remarkably efficient bearing system; articulating cartilage surfaces provide nearly frictionless performance with minimal wear. The low friction properties of the cartilage surfaces are due in part to the boundary lubricant, superficial zone protein (SZP); also known as lubricin or proteoglycan 4 (PRG4). In previous work, SZP localization and cartilage friction...

This paper presents an experimental study on impedance control in both Cartesian and object level with adaptive friction compensation for dexterous robot hand based on joint torque feedback. To adaptively decrease the effects of high friction caused by complex transmission systems and joint coupling, a friction observer is proposed based on the extended Kalman filter (EKF) in this paper. A Cart...

The purpose of this work was to join and assess the development of solid state joints of dissimilar material AA6082 aluminum alloy and AISI 304 stainless steel, via continuous drive friction welding process, which combines the heat generated from friction between two surfaces and plastic deformation. Tests were conducted with different welding process parameters. The results were analyzed by me...

Lubricants are important factors in the tribology of total joint arthroplasty (TJA) surfaces, which are primarily comprised of a polished metallic or ceramic component articulating on an Ultra-High Molecular Weight Polyethylene (PE) surface. Wear particles released from the PE surface are the primary cause of TJA failure. The human body responds to the foreign, microscale particles by activatin...

oint friction is one of the major limitations in performing high J precision manipulation tasks. It affects both static and dynamic performances, and may cause instability when coupled to position or force feedback control. Thus, compensating for joint friction has been one of the main research issues in robot design and control over the years. The aim of this paper is to show how friction comp...

Abstract. Several robotic system applications require manipulators to carry heavy payloads while operating from moving vehicles. These manipulators are mounted on moving/compliant bases, introducing additional degrees of freedom that are not actuated, increasing the complexity of the dynamic modeling and control. In this paper, a control strategy to improve the performance of mobile robotic man...