Volume 2 Issue 2
Authors: Sanjeev Bedi; Amir Khajepour; Hossein Ahari
Abstract: Conformal cooling channels follow the cavity shape and can provide a better cooling performance in injection moulds. Laminated tooling is one of the techniques for manufacturing injection moulds with conformal cooling systems. A laminated tool is made by stacking metal sheets of varying thicknesses from which pre–calculated profiles have been cut. The stacked sheets result in a jagged die surface that has to be finished before use. Although larger number of small thickness sheets result in small irregularities that can be finished easily, it increases the cost of profile cutting process. Therefore, one of the issues in laminated tooling is determination of sheet thicknesses so that the laminated die can be made optimally. In this paper, an optimization method is presented to find the best size of the various laminas based on CAD model surface geometry such that the surface jaggedness and the number of slice is reduced at the same time. The final mould is fabricated based on suggested optimization method. It is then tested to show the improvement in cooling performance as compared to the same die with conventional cooling channels.
Keywords: Laminated Tool; Injection Mould; Conformal Cooling System; Optimization
Authors: Kaixuan Wang; Xiaoyu Zhang
Abstract: The concept and classification of the intelligent assistive devices and rehabilitation robot are introduced in this paper; Domestic intelligence assistive devices include intelligent prosthetics, intelligent orthotics, intelligent walker, assistive devices for smart home environment control and intelligent life assistive devices; Domestic rehabilitation robot includes upper limb rehabilitation robot, hand rehabilitation robot, lower limb rehabilitation robot, robotic smart wheelchair, intelligent nursing bed and daily care robot. The developmental trend of intelligent assistive devices and rehabilitation robot are also introduced.
Keywords: China; Intelligent Assistive Devices; Rehabilitation Robot
Authors: S.P. Popov; F.G. Tcheremissine
Abstract: By joint solution of the Boltzmann and Navier-Stokes equations, flows of rarefied gas about a single flat plate as well as a lattice of the plates are numerically studied. The flows with different Mach numbers and angles of attack are considered. Global characteristics of gas flows and the aerodynamic reactions at the surfaces of the plates are obtained.
Keywords: Boltzmann Equation; Navier-Stokes Equations; Flat Plate; The Lattice of Flat Plates; Transonic Flow; Supersonic Flow
Authors: Yunfeng Li; Yabing Cheng
Abstract: Clearance is an important parameter influencing on the performance of the slewing bearings. The influence law of clearance on load distribution of crossed cylindrical roller slewing bearings was researched．Firstly, the statics model of the bearing with external combined loads was established and a set of nonlinear equilibrium equations were obtained; then, the roller load distribution was calculated by using Newton-Raphson iterative procedure. By using this model and method, the relation of internal bearing clearances and the roller load distribution was analyzed. Results show that with the decrease of the clearance, the number of rollers undertaking the loads begins to increase, and the roller load distribution tends to be homogenized. As the clearance decreases from positive value to negative value, the maximum roller load decreases firstly and then increases gradually. There is an optimal clearance value which is propitious to improve the carrying capacity of the bearing.
Keywords: Slewing Bearing; Clearance; Load Distribution; Carrying Capacity