Advanced Materials Research Vol. 658

Abstract: Creep feed grinding can obtain an excellent grinding performance for its creep feed with high depth of cutting. However the large contact length and large feed result in large amount of heat accumulating in working zone and cause burn on workpiece surface. A series of grinding tests are performed to obtain burn variation with grinding parameters using different grinding wheel and workpiece in this paper. Grinding energy is also recorded and used to evaluate the influence of grinding parameter on burn.

Abstract: Thanks to many industrial benefits that it exhibits, induction heating process is very promising for its potential application in manufacturing production. To understand the industrial context, it is necessary to investigate the process by focusing on simulation and experimental aspects. In fact, this paper presents an original approach able to predict the overtempering zone with analyzing the temperature curves resulting from simulationand the hardness profile achieved by experimental validation. The proposed approach combines experimental validation and numerical simulation applied to 4340 steel disc in order to investigate the overtempering phenomenonand develop a very simplified and practical model able to predict the hardness curve with a fairly good accuracy. The developed model is validated by experimental tests and is used to evaluate the effect of machine parameters on the overtempering.

Abstract: This paper is devoted to develop a 3D model applied to helical gear heated by induction process. The global work is realised by multiphysicsimulation coupling electromagneticfields and heat transfer using Comsolsoftware. This model permits to establish the temperature distribution in function of simulation parameters. The results are very promising since they allow understanding the dissymmetry effect of heating that affect the real hardness profile. Finally, a global sensitivity study about nominal values of machine parameters is conducted to quantify the effect of power consumed by the part on the surface temperature.

Abstract: The objective of this research was to apply the industrial engineering techniques for cost reduction in frozen food industry. Process line survey, line balancing and cost analysis were conducted in each work station to analyze the problem. Data showed that three work stations namely, peeled trim station, arrangement before cooked station, and arrangement in tray station, needed to be improved. Investigation the problems and rate of production at each station the researchers proposed the way to increase the productivity of arrangement before cooked station by setting layout and conveyor installing project. The peeled trim station was proposed to improvement by the labor skilled development and layout design project for process continuous. Also the pre packing arrangement on tray and after freeze station was proposed to improvement by modifying its plant layout and conveyor installing project. It was found that line balancing capability increased from 78.32 % to 90.80 %. The labor skilled development project combined with a design plant layout and conveyor installing system were resulted in reducing 33 persons of labor. It was also showed that the production units cost for the production line can be reduced by 16.65 %. The flow process chart of the production line has showed that delay and transportation activities were reduced from 23.00 % down to 8.70 %.

Abstract: Expected to the non-grid characteristics and pure Lagrangian properties of SPH, the simulation of casting’s filling process would be simpler and precise. In this study, the implementations of SPH method are studied for liquid metal flow and heat transfer during the filling process. The temperature based thermophysical parameters are fitted and add into flow-heat coupling program. The temperature recovery method is included to consider the effect of latent heat. The validation of one-directional heat transfer problem shows that the SPH results have good agreement with the analytical results. The maximum relative error is less than 3%. Finally a circular part is calculated and proved that the SPH model used here works well and has enough precision to capture the behavior of the filling process.

Abstract: In this research, Computer Aided Engineering (CAE) simulation was performed by using the simulation software (Z-Cast) in order to optimize casting design of an automobile part (steering wheel housing) which is well known and complicated to achieve a good casting layout. The simulation results were analyzed and compared with experimental results. During the filling process, internal porosities caused by air entrap were predicted and reduced remarkably by the modification of the gate system and the configuration of overflow. With the solidification analysis, internal porosities caused by the solidification shrinkage were predicted and reduced by the modification of the gate system.

Abstract: The machining accuracy of NC machine can be improved significantly through the error compensation. The kernels of (multi-body system)MBS theories are that the number arrays of low-order body are used to describe the topological structures which are taken to generalize and refine MBS, and the characteristic matrix are employed to represent the relative positions and gestures between any two bodies in MBS. Based on the theory of rigid body dynamics and homogeneous coordinate transformation techniques, the space error model of five-axis gantry NC machine can be established, the modified NC instructions can be obtained and it prepares well ready for the software error compensation and the practical application. Gyratory motion of five-axis NC machine will generate the coupling of translational motion, so it is different from the three-axis NC machine in the process of error compensation and we need to decoupling.

Abstract: Skilled welders can estimate and control the weld penetration based on weld pool observation. This implies that an advanced control system could be developed to control the penetration by emulating the decision making process of the human welder. In this paper a nonlinear dynamic model is established to correlate the process inputs (welding current and traveling speed) and weld penetration in Gas Tungsten Arc Welding (GTAW). An innovative 3D vision sensing system capable of measuring the weld pool characteristic parameters in real-time is utilized. Dynamic experiments are conducted under various welding conditions. Dynamic linear model is first constructed and the results are analyzed. The linear model is then improved by incorporating a nonlinear operating point modeled by Adaptive Neuro Fuzzy Inference System (ANFIS). It is found that the penetration state can be better modeled by the proposed ANFIS model.

Abstract: A new transmission scheme for the myoelectric prosthetic hand is proposed and establishes its 3D parametric model. In order to improve the transmission efficiency and reduce vibration、noise and shock in the situation of the smallest volume. Meanwhile considering the time-varying meshing stiffness of gear pair, lateral vibration, longitudinal vibration and the vibration along the meshing line direction of sun gear and planetary gear, the dynamic analysis model of dual output planetary gear transmission mechanism for the myoelectric prosthetic hand is established. By analyzing the dynamic model, the dynamic characteristics, dynamic response and dynamic load of system are obtained, which lays a foundation for dynamic design of the myoelectric prosthetic hand further.

Abstract: A new scheme of high speed ratio cycloid transmission system used in robot joint is proposed. It has high transmission ratio that is 5 to 10 times larger than 2K-V type cycloid transmission when they has the same volume. The 3D model of the new transmission system is established and its motion condition is simulated, so it verifies the feasibility of the transmission scheme. Considering of the factors such as sliding friction between teeth, gear meshing stiffness and torsion stiffness of the shaft, an 18-degree-of-freedom dynamical model is established, and its dynamics is investigated, the dynamical response and dynamic loads of the new transmission system components considered friction are obtained. Compared with the results having no friction, it can be find that friction between the cycloid gear and the needle teeth impacts the vibration peak value of the new transmission elements in different degree. These provide a good foundation for the dynamical design and performance analysis of a robot.