In this investigation the friction and wear performance of GUR 1020 medical grade ultra-high molecular weight polyethylene (UHMWPE) polymer under dry sliding, distilled water and egg albumen lubrication conditions were evaluated. The sliding experiments were carried out on a pin-on-disc tribometer. The contact configuration used was a polymer pin on a rotating AISI 304L stainless steel disc. We...

Abstract: This paper proposes the discrete dynamic sliding surface control to guarantee the existence of discrete sliding mode and reduce the chattering phenomena for speed control of induction machine drive. In discrete systems, the controller does not control the system during the sampling interval. The great chattering and large control signal are caused by the high switching gain. In this p...

OBJECTIVE To elucidate some of the parameters determining the frictional behavior of passive, active, and interactive self-ligating brackets during sliding mechanics. MATERIALS AND METHODS A custom jig mimicking the three-dimensional tooth movements that occur during sliding mechanics and an Instron testing machine were used to determine the resistance to sliding of six different self-ligatin...

Tribological behaviour of aluminium alloy Al6061T6 reinforced with silicon carbide and alumina oxide particles (10%weight percentage of SiC and Al2O3 particles) fabricated by stir casting process was investigated. The wear and frictional properties of the metal matrix composites was studied by performing dry sliding wear test using a computerized pin-on-disc wear tester. Experiments were conduc...

Frictional sliding along an interface between two identical isotropic elastic plates under impact shear loading is investigated experimentally and numerically. The plates are held together by a compressive stress and one plate is subject to edge impact near the interface. The experiments exhibit both a crack-like and a pulse-like mode of sliding. Plane stress finite element calculations modelin...

Modern wind turbines are designed in order to work in variable speed operations. To perform this task, wind turbines are provided with adjustable speed generators, like the double feed induction generator. One of the main advantage of adjustable speed generators is improving the system efficiency compared to fixed speed generators, because turbine speed can be adjusted as a function of wind spe...

Accurate positioning of the motor requires high control performance for low-speed operation and motor’s parameter perturbation. In the AC motor vector control technology, the nonsingular higher-order terminal sliding mode observer of Insertion Permanent Magnet Synchronous Motor (IPMSM) is put forward based on the object current and voltage values to obtain the rotor position and speed signa. Th...

With the aim to achieve high dynamic performances under system uncertainties and load torque even at very low speed range, this paper presents a novel robust sensorless speed vector control strategy for single phase induction motor (SPIM). The proposed strategy includes a speed controller and a model reference adaptive system (MRAS) estimation algorithm of rotor speed both are based sliding mod...