The aim of this project is to fabricated an aluminium-copper bimetal through the fusion method and examine its performance. An aluminium-copper-aluminium bimetal was built by the laser cladding method. The laser power as well as the annealing time effects on its interfacial properties of the bonding’s formed through the laser cladding were investigated. To fabricate the multilayer bimetal, the laser beam characteristic including the beam radios, and Transverse Electromagnetic Mode (TEM), and focusing conditions were considered in a heat source model. The model was, next, integrated within SYSWELD package to predict the temperature distribution and clad bead profile during the laser cladding of the pre-placed copper powder layer on the aluminium substrate. After the samples preparation, the intermetallic compounds formed at the joints were explored through the Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) processes. Based on the experimental results, a laser power increase from 1100 W to 1150 W increases the intermetallic compound width, while an increase of 1150 W to 1200 W does not have much effect on the width. Also, increasing the annealing time results, increases the intermetallic compound thickness. In addition, based on obtained experimental results, four specimens are detected at the bimetal interface, one of which has 73.4 % copper and 26.1 % aluminium. The results also indicate that, with increasing both the laser power and annealing time, the electrical resistance of the samples decrease. پرونده مقاله

Stroke is one of the most common diseases among the elderly with high personal and societal costs. In recent years, robotic rehabilitation for stroke has become an active area of research for assistance, monitoring and qualifying the rehabilitation treatments. The key issue needed for improving rehabilitation system is that patient feedback should be taken into account by the robotic rehabilitation systems for providing rehabilitation treatment. Changes in the delivery of rehabilitation treatment are an important issue since the patient or specialist should be able to express their sense about doing things and apply the needed improvements in treatment. Therefore, in this study, a three degree-of-freedom (3-DOF) exoskeleton design of a thumb has been investigated. Then, a control structure is provided for greater security in which the patient feedback is evaluated in order to make necessary automatic changes in method of treatment (changing speed and force). In this design, a versatile framework with high performance is offered to simultaneously control thumb force and position regarding the patients’ feedback. This may help to keep the patient in the treatment process, reduce interventions and therapist caseload, effective automatic transmission of treatment and pain relief during the course of treatment. The results of the study suggest that the force and speed on the thumb can be changed during the rehabilitation period according to the patient's needs. This advantage may be considered as an essential step for improvement of the rehabilitation efficiency. پرونده مقاله