bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation and Experimental Analysis of the Effect of Channel Width on Flow Field in Laser Cutting
Authors: Sheng X.J. , Hu Jun
Published: August 2009

A three-dimensional axial symmetrical model of laser cutting is established by adopting N-S equation in the paper, and numerical simulation is put up to analyze the flow field of assist gas in cutting channel. The investigation reveals the law about how channel width affects the dynamic characteristic of gas jet in the cutting process, and the distributions of pressure and velocity of gas jet with different channel widths are shown in the study. The study shows that the intensity of compressed wave and expanded wave in cutting channel declines remarkably with channel width increasing, and the kinetic energy at channel surface drops while the cutting quality is deteriorated. A taper nozzle with cone angle of 30°and a convergence nozzle comprised a parabola equation of are designed for the laser cutting experiment. The experimental results are given at the end of the paper.
Effect Mechanism of Nitrogen Gas on Chip Formation in High Speed Cutting of Ti6Al4V Alloy Based on FEM Simulation
Authors: Zhao Wei , He Ning , Li Liang
Published: August 2009

Titanium alloys are known for their strong chemical reactivity with surrounding gas due to their high chemical affinity, especially in dry machining. This paper describes a study of chip formation characteristics under nitrogen gas media when machining Ti6Al4V alloy with WC-Co cemented carbide cutting tools at high cutting speeds. Based on the experimental study, a finite element model of two-dimensional orthogonal cutting process for Ti6Al4V alloy at different cutting conditions was developed using a commercial finite element software Deform-2D. Saw-tooth chips with adiabatic shear bands were produced in both experiments and simulations. And the enhanced cooling and anti-frictional effects of nitrogen gas upon the high speed cutting process of Ti6Al4V alloy were analyzed. Results of this investigation indicate that the anti-frictional performance of nitrogen gas has a significant effect on chip formation when machining Ti6Al4V alloy at high cutting speeds. Compared to air, Nitrogen gas is more suitable in improving the contact conditions at chip-tool interfaces and in increasing the shear band frequency of chip formation during high speed cutting of Ti6Al4V alloy.
Finite Element Analysis of Residual Stress in Diamond/Steel Brazed Joint
Authors: Chen Yan , Xu Jiu Hua , Fu Yu Can , Su Hong Hua , Ding Wen Feng
Published: August 2009

In the application of brazed diamond tools, residual stress caused by differences in materials properties is an important factor in obtaining good brazing quality. The residual stress in diamond/steel brazed joint is studied by means of finite element method and Raman spectroscopy in this paper. The comparison between the results from the simulations and the measurements shows that a good agreement has been reached. Tensile stress concentration at the diamond edge near interface was observed. High residual stress concentration may cause cracks in diamond. Actually, cracks in diamond caused by brazing residual stress after were observed. The stress concentration of the joint must be reduced to obtain good brazed joint. The change of brazing atmosphere or to adopt the soft brazing alloy will reduce the stress concentration.
The Optimal Model of Tool Paths Generation for Pocket Milling
Authors: Huang Xiang , Lin Z.X.
Published: August 2009

This paper describes an integrated method to determine optimal cutting parameters for milling pocket based on minimum cutting time. The main constraints entailed in real cutting, such as chatter free, uncut free tool paths, cutter and machine tool limitations, are included into the optimal model. The optimal parameters (depth of cut, width of cut, spindle speed) are inserted into the tool paths generation directly for four kinds of conventional cutting modes (Zig and Zig-Zag parallel cutting mode, inwards and outwards spiral pattern modes). According to the fact that the first cut in every cut level is slotting milling, the milling areas are divided into slotting milling area and general milling area. This dynamically corrected tool paths generation method changes the order of conventional tool paths, so different cutting parameters are used in slotting milling and general milling areas. The case study has demonstrated that the proposed methods can identify the optimal milling conditions and generate tool paths automatically and result in minimum milling time.
The Effects of Machining Parameters on Measured Temperatures and Energy Partition in Circular Sawing of Granite
Authors: Fang Cong Fu , Xu Xi Peng
Published: August 2009

An investigation is reported of the temperatures in the sawing of granite with a circular sawblade under a wide range of machining parameters including cutting fluids and cutting modes. Temperature responses in the sawing contact zone were measured using a foil thermocouple. The measurement was subsequently used to analyze the influence of operating parameters on the sawing temperatures and the energy partition. For either down-cutting or up-cutting, either with cutting fluids or without cutting fluids, the temperatures in the sawing zone were found to increase with depth of cut, sawblade speed, and workpiece speed. The maximum temperature in the sawing without cutting fluids was found to be up to 400°C whereas it was reduced to around 250°C while using cutting fluids. The energy partition conducted to the workpiece is about 7% ~10% in dry sawing and about 2% ~5% in wet sawing.
Effect of SiC Particles on the Machining of Aluminum/SiC Composite
Authors: Zhang Gao Feng , Tan Yuan Qiang , Zhang Bi , Deng Zhao Hui
Published: August 2009

The objective of this study is to experimentally investigate the effect of reinforced SiC particles on the machining of Aluminum/SiC composite (15% volume ratio of SiC particles with average grain size 15m). Aluminum/SiC composite and aluminum metal were milled by a tungsten carbide endmill in this study. Based on the surface observation and surface roughness inspection, it is found that the machining parameters of Aluminum/SiC composite have optimum values, and that the surface roughness of aluminum/SiC composite is smaller than that of aluminum metal. when feedrate and depth of cut are smaller than limited values, satisfactory surface finish can be attainable, however, as the depth of cut and feedrate increases, the microcracks are first initiated at the interface of SiC particles and aluminum matrix, and then periodically macrocracks are formed on the machined surface, The damage mechanism during the machining of aluminum/SiC are discussed in this paper.
The Mechanism of Polymer Particles in Silicon Wafer CMP
Authors: Xu Xue Feng , Chen H.F. , Ma H.T. , Ma B.X. , Peng Wei
Published: August 2009

In order to increase the material removal rate of silicon wafer, composite abrasives slurry was used in CMP. Zeta potential of polymer particle was measured and interaction potential energy between silica abrasives and polymer particles in slurry were analyzed and calculated. Adsorptions between silica abrasives and polymer particles were observed with TEM. CMP experiments had been taken to analyze the effects of polishing parameters (the concentration of colloidal silica and polymer particle, the pressure and the speed of polishing) on the material removal rate. The mechanism of polymer particle in polishing was elaborated. Experimental results indicated that PS, PMMA and BGF polymer particles could adsorb silica abrasives in slurry. Silica shell/PS core, silica shell/PMMA core and silica shell/BGF core particles could be used to formulate composite abrasives slurries. The material removal rate with composite abrasives slurry was higher than that of single abrasive slurry. The maximum material removal rate was obtained with silica shell/BGF core composite abrasives slurry.
Motion Model and Numerical Simulation of Fluid and Abrasive Particle in Near Wall Region
Authors: Ji Shi Ming , Xu J.L. , Zhang Li , Jin Ming Sheng , Yang Y.H. , Wang Y.
Published: August 2009

The paper discusses the near wall region of soft abrasive particle flow in weak force finish machining method. Turbulent flow morphology in near wall region of rectangular channel with different viscosity is numerically simulated and compared. Through the analysis of kinetic equation of abrasive particle, the abrasive particle motion trace of different diameter in turbulent flow with different viscosity is simulated and compared. The result reveals the condition under which the fluids with different viscosity can form Turbulent flow is different. The greater the viscosity is, the greater the velocity needed is. Also the quantitative relation of velocity and flow volume is available to determine the pump parameter in abrasive particle flow machining. Fluid at wall has pressure and shear stress on work piece. The greater the viscosity and velocity is, the greater the wall pressure and shear stress is. So it is helpful to make material removal on work piece surface. But the greater the viscosity is, the greater the velocity attenuation of abrasive particle is. Abrasive particle mainly move along the flow direction with the movement of fluid. The velocity attenuation of larger diameter abrasive particle is much than the smaller particle but the latter can maintain greater velocity in a longer distance favorable for collision with the work piece surface salient.
Research on Vector Blending Algorithm of Velocity for Acceleration and Deceleration of High Speed Machining
Authors: Ren Kun , Chen H.G. , Chen Wen Hua , Pan Jun
Published: August 2009

To guarantee the efficiency and accuracy of machining in high speed machining, a novel vector blending algorithm for velocity smooth link is proposed. Based on efficient acceleration/deceleration technique for a single distance movement, the desired acceleration/deceleration characteristics can be selected. According to acceleration/deceleration characteristics, two different acceleration/deceleration profiles for two corresponding distance movements are constructed respectively. Under the condition of length of movement, highest velocity and direction of motion, two different acceleration/deceleration profiles are blended. On-line implementation results show that the proposed approach makes velocity link smoothly and efficiency and accuracy of machining can be guaranteed.
Calculation of Heat Distribution in High Speed Cutting Based on Finite Element Method
Authors: Liu Wang Yu , Liu X.K. , Li Jing , Zhang Yong
Published: August 2009

Combined the analytic method with the finite element method, the data necessary for calculating the heat distribution ratio for high speed cutting was mined first, and the experimental result was used to validate the authenticity of finite element modeling. Then, the ratio of heat distribution for high speed cutting based on the analytic model was obtained by customizing the special subroutine developed by the authors, which provides a new method for calculating the heat distribution.
High-Speed and High-Accuracy EDM of Micro Holes by Using a 5-DOF Controlled Maglev Local Actuator
Authors: Zhang X. , Ueyama Y. , Shinshi T. , Shimokohbe Akira , Sato T. , Miyake H. , Nakagawa T.
Published: August 2009

The objective of this study is to realize high-speed and high-accuracy electrical discharge machining (EDM) of micro holes using a combination of a conventional EDM machine and a maglev local actuator. In this paper, the conventional EDM machine and the wide-bandwidth, high-precision, 5-DOF controlled maglev local actuator are combined and cooperatively controlled. Then to accelerate the debris ejection from the machined holes, the driving methods of the axial jump and radial vibration of the electrode are discussed. The experimental results show that the maglev local actuator can adjust the gap between the electrode and a workpiece speedily, and the machining speed is improved by 434.2%, compared with conventional EDM machine. Moreover, by the jump and the circular motion of the electrode, the debris ejection can be accelerated, the abnormal electrical discharge can be avoided, and the machining speed also is improved by 580.3%.
Study on Micro Reversible Electrical Discharge Machining Method for the Fabrication of Micro Structures
Authors: Peng Zi Long , Wang Zhen Long , Wang Yu Kui , Dong Ying Huai , Chen H.
Published: August 2009

A reversible machining method using micro electrical discharge machining (EDM) was developed. This new method can achieve depositing or selective removing of metal material for the fabrication of micro structures. It is easy to transform the machining process from deposition to removal in one EDM machining system. In micro EDM deposition process, brass, tungsten and steel material can be deposited successfully. The deposited material has compact fine texture and combines close to workpiece. Then, micro complex structures by series deposition strategy and sub-deposition strategy were deposited. In the selective removal process, the machining effects of different working mediums were researched. Results show that the machining effect in liquid medium is better than that of in air. Finally, using the micro reversible EDM process, a micro square column with 0.070mm in side length, 0.750mm in height and a micro cylinder with 0.140mm in diameter, 1.180mm in height were fabricated.
A Novel Power Supply for High Speed Drilling Electrical Discharge Machining Base on Pulsed Width Modulated
Authors: Huang He , Bai Ji Cheng , Lu Ze Sheng , Guo Yong Feng
Published: August 2009

In this paper, a novel Pulsed-Width-Modulated (PWM) half-bridge High Speed Drilling Electrical Discharge Machining (HSDEDM) power supply has been developed. This power supply has excellent features that include minimal component count and inherent protection. This topology has an energy conservation feature and eliminates the output bulk capacitors and current limiting resistances. Energy used in the erosion process will be controlled by the switched Insulated Gate Bipolar Transistors (IGBTs) in the half-bridge network and be transferred to the gap between the tool and work-piece. The relative tool wear and machining speed of our proposed topology have been compared with that of a normal power supply with current limiting resistances.
A Half-Bridge Isopulse Power Supply For WEDM
Authors: Li C.J. , Guo Yong Feng , Bai Ji Cheng , Lu Ze Sheng
Published: August 2009

In Wire Electro Discharge Machine (WEDM), as the big randomicity of electro discharge, single discharge energy is various. In this paper a resistor-less and half-bridge power supply is investigated based on pulse width modulation(PWM), whose single discharge energy is equal , adopting discharge control strategy of breakdown waiting. And the experiment shows the cutting speed and surface roughness of this isopluse power supply is superior to that of traditional isofrequency power supply.
Machining Deep Micro Holes by EDM with USM in Inversion Installing
Authors: Jia Bao Xian , Wang D.S. , Guo Jing Zhe
Published: August 2009

In order to obtain micro holes with high aspect ratio, a new technique of machining deep micro holes by combining EDM (Electrical Discharge Machining) with USM (Ultrasonic Machining) in inversion installing is researched. The workpiece is over the electrode. The ultrasonic vibration is affixed to the electrode. The workpiece and electrode are all immersed in working liquid. The debris generated by EDM is dropped out the hole from the gap between the electrode and the hole wall by the gravity and the pumping effect of ultrasonic vibration, so as to increasing the machining velocity and machined depth. The structural features of the machining device are described, and the exploratory experiment is carried out. The corresponding process relations are found out, which can provide references for further study of this technique. The micro holes with larger than 25 in aspect ratio are machined.
Experimental Studies on Dry WEDM in Improving Surface Quality
Authors: Wang Tong , Lu Yu Mei , Chen Q. , Zhou S.H.
Published: August 2009

This study investigates the dry wire electrical discharge machining (WEDM) in multiple cut. To improve surface quality with high-speed WEDM (HS-WEDM), a new procedure as Gas-liquid Combined Multiple Cut (roughing is processed in dielectric liquid, and semi-finishing is in liquid or gas, while the finishing is in gas) is presented. Effects of pulse duration, pulse interval, peak current, offset, wire winding speed and wire length on roughness, straightness and removal rate had been studied in dry and wet conditions. Experiment results show that multiple cut with dry WEDM in semi-finishing and finishing can improve surface roughness significantly.
Prediction of the Residual Stress in Grind-Hardening with Thermal-Mechanical-Phase Transformation Stress Coupled Analysis
Authors: Ge Pei Qi , Zhang Q. , Zhang L. , Zhang Jian Hua
Published: August 2009

Grind-hardening is a type of composite technology, which utilizes the dissipated heat in the grinding zone for hardening of the workpiece surface layer. The temperature of the workpiece surface, when heated by the grinding, is higher than the austenitizing temperature for short time, then it is lowered by quick cooling causing martensitic transformation to happen in the surface layer of the workpiece. The residual stress is formed by the thermal stress, phase transformation stress and mechanical stress in the grind-hardening layer. In this paper, the forming mechanism of the residual stress in grind-hardening technology is analyzed in theory; the residual stress field in the surface layer is calculated by the finite element, according to changes in the specific volume of the microstructure, the temperature field and the temperature history of the surface layer at different depths. The temperature field is achieved by computer simulation technology. The result of residual stress calculations indicates that the change tendency of the grind-hardening residual stress in the finite element analysis is consistent with the experiments.
Study on Numerical Controlled Electrochemical Turning
Authors: Kang Min , Yang Yong , Fu X.Q.
Published: August 2009

A preliminary study of Numerical Controlled Electrochemical Turning (NC-ECT) technology was presented in this paper. NC-ECT is suitable for machining revolving workpieces which are made of difficult-to-cut materials or have low rigidity, and it is difficult or expensive for machining these workpieces by use of traditional turning or traditional Electrochemical Machining (ECM) method. To carry out the study, an experimental setup was developed on the basis of a common lathe, and a kind of inner-spraying cathode with rectangle section outlet was designed according to the process of machining cylindrical surface. First, the NC-ECT method was simply described. Then, considering the structure of the cathode and the process of machining, the method for calculating the inter-electrode gap in machining the cylindrical surface was given. Finally, the experiments of machining the cylindrical surface were carried out. Experiments showed that the calculated inter-electrode gaps are well consistent with the actual value of the machining process, which decreases with the increase of the rotational speed of workpiece and increases almost linearly with the increase of the working voltage. Experiments also showed that the inter-electrode gap keeps a certain relationship with the working current, the inter-electrode gap can be controlled according to working current in the machining process.
Experimental Investigation on Metal Coating by Means of ESD
Authors: Li Y.Y. , Guo Z.N. , Liu G.Y.
Published: August 2009

The technology of electro-spark deposition has been investigated and the thickness of H13 steel coating up to 16.2μm has been achieved by applied SH-1000 electro-spark deposition power. It analyzed the effect of parameters such as voltage, discharge frequency, argon gas flow and rate deposition on the deposition thickness. The optimum deposition parameters have been selected through the orthogonal design. In order to improve coating quality, a novel method based on ultrasonic-assisted electro-spark deposition has been put forward.
Development of Ultra-Short Pulse Power Supply Applicable to Micro-ECM
Authors: Zhang Yong Jun , Tang Yong Jun , Liu Xiao Kang , Guo Z.N. , Li F.
Published: August 2009

A nanosecond pulse power supply for micro-ECM (Electrochemical Machining) has been developed, and the minimum pulse on-time is 50 ns. After the influence of ultra-short pulse on micro-ECM was analyzed, complementary chopper circuit was presented to avoid waveform distortion, which can achieve higher pulse frequency. A fast protect circuit was designed, and its response time is less than 5μs, which can avoid damaging workpiece and electrical components by switching off machining voltage and step motor as soon as a short circuit was detected. A series of ECM experiments using the power supply have been carried out, and results of test have proved that high frequency, short pulse width power supply helps to achieve better quality surface, higher machining accuracy.
Prediction on Residual Stress and Fatigue Life of Magnesium Alloy Treated by Laser Shot Peening
Authors: Jiang Su Qing , Zhou Jian Zhong , Fan Yu Jie , Huang Shu , Zhao J.F.
Published: August 2009

Numerical study on fatigue life of ZK60 magnesium alloy plate before and after laser shot peening (LSP) was carried out in this paper. Based on the FEA model, residual stress field induced by LSP was analyzed, the fatigue life and position of weak area were predicted with ABAQUS software and MSC.Fatigue code, respectively, and the processing parameters were optimized. The results show that the fatigue life of ZK60 sheet metal by single LSP with one side and both sides increased by 72.9% and 78.5% compared with the untreated sample respectively. The size and depth of compressive residual stress increase with the increment of peening number, but when the peening number gets to a certain value, the residual stress reaches saturation and the fatigue life increase no longer significantly.
Applied Research of Full Digital Electric Control Systems on Rebuild Machine Tool
Authors: Wu Y.C. , Zuo Zhi Yong , Sun Y.
Published: August 2009

Taking account of the situation of many old-fashioned imported machine tools, this paper proposes some favourable methods of rebuilding equipment. In theory and practice, with full digital electric system of modern automation technology, rebuilt equipments are easy to operate and reduce energy consumption, raise production efficiency. It realizes the aim of Environment-friendly and resource-economical. In this paper, it also gives three typical examples of rebuilding equipment, table planning machine made in Germany, D2300 lathe and 745A slotter made in Russia. Some pragmatic issues have been discussed, e.g. design optimization for speed regulation of main drive, position finding of cutter frame and synchro control between lathe tools feeding and lathe chuck turning. Finally, it gives the results of the operational curves of rebuilding equipment and relevant data.
An Algebraic Method for Direct Position Analysis of the General Stewart Platform Manipulator Robot
Authors: Huang Xi Guang , He Guang Pin , Liao Q.Z.
Published: August 2009

Stewart platform manipulator robot is a six degree of freedom, parallel manipulator, which consists of a base platform, a mobile platform and six limbs connected at six distinct points on the base platform and the mobile platform respectively. The direct position analysis problem of Stewart platform relates to the determination of the mobile platform pose for a given set of the lengths of the limbs. In this paper, we present a concise algebraic method for solving the direct position analysis problem for the fully parallel manipulator with general geometry, often referred to as General Stewart platform manipulator. Based on the presented algebraic method, we derive a 40th degree univariate polynomial from a determinant of 20×20 Sylvester’s matrix, which is relatively small in size. We also obtain a complete set of 40 solutions to the most general Stewart platform. The proposed method is comparatively concise and reduces the computational burden. Finally the method is demonstrated by a numerical example.
A New Parallel Kinematic Machine UPS-2RPS and Kinematics Analysis
Authors: Feng Zhi You , Gao Zhi Guo , Yang Ting Li , Zhang Ce
Published: August 2009

A new parallel kinematic machine UPS-2RPS with serial input limb is presented, the topological structure characteristics are described. The mathematic model of inverse position solution is derived. The workspace of the mechanism is analyzed and researched by results of MATLAB and Pro/E simulation, The research will be of great significance to promote its novation, application and spread .
Analysis and Optimal Design for the Static Stiffness of a 2UPS-UPR Parallel Machine Tool
Authors: Zhao Liang , Gong Ya Dong , Cai Guang Qi
Published: August 2009

The stiffness model of the parallel machine tool is established by static analysis, the static stiffness analysis is carried out through numerical Simulation and the stiffness distribution is given. On the basis of this, the optimal objective is given which is the average of 729 values of -axis stiffness and -axis stiffness corresponding to 729 positions in the workspace. With MATLAB software, the effects are simulated which the structural parameters of the parallel machine tool have on their stiffness, their change rules are gained, and this provides a basis for the structural design of this type of machine tools.
Research of Quick-Return Mechanisms Using for Automatic Cooking Robot
Authors: Lin X.R. , Li Bing , Zhao Wei
Published: August 2009

At present, almost all the cocking work is completed in smoke-filled kitchen, which is a time-consuming and laborious work. However, with the development of automatic and robotics technology, how to apply the relevant technology to the field of cooking has become increasingly urgent. The purpose of this paper is to apply quick-return mechanisms to automatic cooking robot, so as to obtain the realization of the movement of reversing pot. And the main three parts of the study are: the analysis of several typical quick-return mechanisms and the description of their possibility in realizing the movement of reversing pot; dynamic simulation analysis of some kinds of mechanisms, which can cover the basic requirements of the movement of reversing pot, is done so as to determine their functions in realizing the movement of reversing pot and their different characteristics; through taking the typical Sharper(quick-return swing guide) agency as an example and using Pro/E and Adams to realize the dynamic simulation and analysis, the key parameters of such bodies is selected and can provide the basis for the further study of automatic cooking robot.
Research on the Influence of Shields to Thermal Equilibrium of CNC Machine Tool
Authors: Liu Yang , Lu Ying , Bi Xue Feng , Cai Guang Qi
Published: August 2009

In order to investigate that shields have the effect on the thermal equilibrium of CNC machine tool, this paper applies the theory of heat transfer and finite element analysis to analyze the thermal characteristics of CNC lathe CK40A/1000. By ANSYS software, the temperature distributions of spindle engine, headstock and bearing at thermal equilibrium with/without shields are obtained. By analyzing thermal equilibrium patterns and experiments, the temperature of spindle bearings with shields are 3-4 higher than without shields at thermal equilibrium. And shields have less influence on the temperature gradient of tool inner thermal sources.
Dynamic Characteristic Analysis and Validation of Spindle Assembly of NC Machine Tool
Authors: Zhang Yao Man , Wang S.H. , Liu Yong Xian
Published: August 2009

One of the important factors resulting in the performances of the machinery is its dynamic characteristics. The spindle assembly is one of the usual parts of NC machine tool, so its dynamic-static characteristics will affect the performances of machine tool. The study is based on a NC machine tool produced by a certain plant of machine tools. The finite element dynamic analysis model of spindle assembly was developed by introducing two or three groups of circumferential spring damper elements which are arrange at different angle around the spindle, and the effect of different supporting conditions and different arrange angle on the modal analysis of the spindle assembly were discussed. The finite element analysis on spindle and spindle assembly has been made to confirm its dynamic characteristics. Then the finite element analysis models are validated by some experiments.
Dynamical Sliding Mode Control of Mobile Manipulators
Authors: Mei Hong , Wang Yong
Published: August 2009

A solution to the problem of the elimination of the chattering effect and the improving of the convergence speed for sliding mode control is presented in this paper.A new dynamical sliding mode controller is developed which takes the first derivative of the control signal instead of the actual control as control and results in smoothed control inputs to the given system.A new nonlinear sliding mode surface is devised which can improve the convergence speed in the sliding phase.Exponential reaching law is taken to determine the control law which can improve the convergence speed in the reaching phase.A mobile manipulator with two arms is taken as an example to track a given trajectory with the proposed controller. It is found that the new developed method has a high convergence speed and the chattering is also reduced greatly.
A Study of Topology Optimization Design for the Wafer Handling Robot Arm
Authors: Cong M. , Wang T.J. , Zhang Cheng Shuang
Published: August 2009

To attain the optimal shape of the robot arm with the minimum compliance and the suitable weight and lower the possibility of vibration, this paper applies the homogenization method to describe the topology optimization design of the wafer handling robot arm which modal analysis is carried out subsequently. We deduce and establish the mathematical model of the topology optimization based on the homogenization method and calculate it by ANSYS. The results suggested that the compliance and the weight were reduced. Then we calculated the modal analysis of the optimized and non-optimized robot arms, and it was found that the first sixth natural frequencies of the optimized robot arm all increased whereas the probability of the natural vibration declined. It is concluded that the topology optimization design of the wafer handling robot has been shown to be effective in improving the stability of the robot arm.
A Study on the Monitoring Technology of Extra-Large Deep Hole Drilling Using the Tilt Sensor
Authors: Kim Nam Hun , Shin Il Sik , Park Jeong Woo
Published: August 2009

This study is on the configuration of deep hole drilling system for machining of extra-large common rail fuel supply pipes. Machining conditions for deep hole drilling were deduced and stability of the developed system was verified through measurement of machining surface roughness. Also, a tilt sensor was used for real-time monitoring on machining of deep hole drilling. Machining state was evaluated through composition of a control system for signal feedback.
Adaptive Parameter Estimation and Position Control of Induction Motors Based on Passivity Theorem
Authors: Chen Jenn Yih , Lee Bean Yin
Published: August 2009

This paper presents the passivity-based rotor resistance and mechanical paramters estimation, and the position control for induction motors. Firstly, the input-output linearization theory is employed to decouple the rotor flux amplitude and the rotor position at the transient state. An open-loop current model flux observer then estimates the rotor flux. Furthermore, we adopted the gradient algorithm to design adaptive laws to estimate the rotor resistance, moment of inertia, viscous coefficient, and load torque. The passive properties of the feedback connection of the rotor flux observer to the rotor resistance estimator, and the position controller are analyzed by the passivity theorem. According to the properties, the overall control system is proved to be globally stable without using Lyapunov-type arguments. Finally, experimental results are provided to show that the proposed method is robust to variations of the mechanical parameters and load torque disturbances. Moreover, good position tracking response and parameters estimating characteristic can be obtained.
Analysis of Dynamic for the Main Shaft Systems in XK7132 NC Drill and Milling Machine
Authors: Liu W.N. , Gu D.W. , Yang Li Feng , Zhang Shu Ren , Li Y.
Published: August 2009

Experimentation modal analysis is the major technique for the mechanism dynamic properties. This study proceeds dynamic analysis in XK7132 NC Drill and Milling Machine with experimentation modal analysis. Thereby it gets the modal parameter of the tool of main shaft systems. It takes clearly reference for the rationalization design of main shaft systems in NC drill and milling tool.
Tool Wear Monitoring: An Automated System Based on Multiple Cutting Force Parameters and Machine Vision Technique
Authors: Liang Yu Teng , Chiou Yih Chih
Published: August 2009

This study proposes a tool wear automatic monitoring system based on multiple parameters analysis of cutting force and machine vision technique. A drilling model of cutting parameters (cutting force, coating layer, spindle speed and feed rate) and tool condition (focusing on tool flank wear measurement and analysis) was developed. The experimental design methods developed in this study can be used to optimize cutting parameters efficiently and reliably. The drilling model based on cutting parameters was constructed using Taguchi method. This method enabled evaluation of wear status based on the actual force obtained from a dynamometer. The derived relation is useful for in-process wear monitoring. Tool wear dynamics are extremely complex and not yet fully understood. Therefore, vision-based tool wear monitoring techniques can help elucidate wear progression. In this study, a drilling model based on the machine vision technique was used to establish a direct relation between cutting parameters and tool wear. The object of the experiments was to measure the flank wear of cutting tools with various coatings. The experimental results show that the monitoring system clarifies the relationships between cutting force and multiple cutting parameters.
Research of Gasoline Engine Ignition Control Based on Neural Network
Authors: Wang Y.Y. , Yang Jian Guo , Song B.Y.
Published: August 2009

In order to realize the precise ignition control of gasoline engine, an ignition advance angle BP (Back Propagation) neural network model is built. The improved LM (Levenberg-Marquardt) learning algorithm is used in the model to increase the neural network performance. The neural network model is trained and tested by matlab program. For a variety of inputs, the trained ignition advance angle neural network can carry out correct outputs. Compared with the experimental ignition advance angle, the maximum error of the neural network ignition advance angle is less than 5%. Compared with the experimental map method, the ignition advance angle neural network has the advantage of online modifying the value of ignition advance angle, so it can make the gasoline engine acquire the best ignition advance angle on various working conditions. The results show that the ignition advance angle neural network model established in this paper is effective and accurate. The performance of gasoline engine can be improved ultimately.
Experiment Research on the Drill Fracture Criterion in Inclined Hole Drilling
Authors: Zhang Peng , Guo Xing Yu , Zhang De Yuan
Published: August 2009

There are many inclined holes in modern manufacturing industry. Due to the special machining state of drilling out, the drilling jigs and other auxiliary mechods can not been used. There is intermittent cutting for a long time during drilling out, and the axial force and torque are also impact force, which cause the drill to break. The experiments results showed that the axial force and torque were also been incresed, especially the later, which is the principal factor of the drill fracture. So it is the experimental foundation for further to control and protect the dill to break.
On the Bifurcation and Stability of Periodic Motion of the Rotor-Bearing System with Rub-Impact and Oil Whirl
Authors: Liu Chang Li , Zhang X.L. , Cui L. , Jiang J. , Zheng J.R.
Published: August 2009

In this paper, the dynamic model of rotor bearing system with rub-impact and oil whirl is formulated. Continuation-shooting method for the periodic solution of nonlinear non-autonomous system is used to obtain the bifurcation and stability of the periodic motion of the rotor-bearing system. The effect of the unbalance and rotor/stator clearance on the bifurcation and stability of the periodic motion of the rotor bearing system are analyzed respectively. The results obtained are compared with those of rotor-bearing system with oil whirl fault.
Design and Test of Express Elevator Control System
Authors: Liu Tun Dong , Han Y. , Su H. , Wang Ying
Published: August 2009

In order to meet the increasing requirements for express elevator control system and its intelligence and security, ARM chip is applied to construct hardware platform of elevator's main-board in this paper. BootLoader and the uCLinux are transplanted to this platform, and CAN-Bus and other related drivers are designed. A single elevator's operation algorithm is presented to achieve the elevator control logic. And the store and access of parameters of elevator are accomplished by real-time SQLite database. The main high-speed counting circuit is designed based on CPLD while the auxiliary one is based on AVR MCU, which guarantee the stability and reliability of the system. The operational results in elevator simulator verify the feasibility and efficiency of the control system.
The 3D Reconstruction Technology for the Bone SCT Image
Authors: Wang W.J. , Ge Zheng Hao , Jiang Meng , Li C.L.
Published: August 2009

The key technologies about the 3D reconstruction of the bone SCT image for fast biological manufacture is discussed in this paper. Methods for 3D bone reconstruction are studied. Finally, an appropriate method based on bone SCT image is gained. SCT image is preprocessed, binary treated, and contour abstracted by SCT image abstraction system. This method can achieve following aims: processing outline data collection, reversing bone 3D surface and reconstructing 3D bionic model. The example in this work has shown how the 3D model of a bone is obtained through plane reconstructing successfully. Image processing algorithm is concluded, thereby providing necessary information for 3D reconstruction of bone SCT image.
Fabrication of a RP-Based Biomimetic Grafting Material for Bone Tissue Engineering
Authors: Ma Xing , Hu Y.Y. , Wu Xiao Ming , Liu J. , Xiong Zhuo , Yan Y.N. , Lv R. , Wang J.
Published: August 2009

Three-dimensional (3D) highly porous poly (DL-lactic-co-glycolic acid)/tricalcium phosphate (PLGA/TCP) scaffolds were fabricated using a rapid prototyping technique (RP). The biopolymer carriers (4mm×4mm×4mm) subsequently were coated with collagen type I (Col) to produce PLGA/TCP/Col composites and utilized as an extracellular matrix for a cell-based strategy of bone tissue engineering. Autologous bone marrow stromal cells (BMSCs) harvested from New Zealand white rabbits were cultured under an osteogenic condition (BMSCs-OB) followed by seeding into the structural highly porous PLGA/TCP/Col composites (i.e. PLGA/TCP/Col/BMSCs-OB). Scanning electron microscopy observation found that the RP-based scaffolds had appropriate microstructure, controlled interconnectivity and high porosity. Modification of the scaffolds with collagen type I (PLGA/TCP/Col) essentially increased the affinity of the carriers to seeding cells, and PLGA/TCP/Col composites were well biocompatible with BMSCs-OB. The PLGA/TCP/Col/BMSCs-OB constructs were then subcutaneously implanted in the back of rabbits compared to controls with autologous BMSCs suspension and carriers alone. As a result, histological new bone formation was observed only in the experimental group with PLGA/TCP/Col/BMSCs-OB constructs 8 weeks after implantation. In the control group with scaffold alone only biodegradation of the carriers was found. Therefore, these results validate our bio-manufacturing methods for a new bone graft substitute.
The New Technology of Engineering Ceramic Machining by Electrode Micro-Detonation
Authors: Tian Xin Li , Yang Jun Fei , Liu Chao , Yu Ai Bing
Published: August 2009

With reference to the principle that the strong detonation wave generates the transient dynamic high pressure, the small power pulse power supply and the electrode micro-detonation wave generator are developed. The engineering ceramic material machining with low cost is realized successfully with the devices. It is shown from the study results that there is a degenerative layer about 0.25~0.45mm thick, which is composed of amorphous phases and crystalloid Si and can be machined and removed with the ceramic tool after micro-detonation machining. There are obvious transverse cracks near the interface of the degenerative layer and the matrix, but the cracks along the depth direction are not found. The performance of the degenerative layer is roundly analyzed and its removing mechanism is primitively discussed.
Development of CNC System for Machining of Grooves in Automobile Synchronization Regulators Sleeve
Authors: Chen Dong Xiang , Li Jia , Zhao Chen
Published: August 2009

On the basis of analyzing the shortcomings of the current technics for grooves machining, this paper deals with the development of Numerical Control System for machining of grooves in automobile synchronization regulator sleeve, which holds first-rate technics. In order to improve efficiency and precision of grooves machining and reduce cost of the cutter, Hypocycloid-based technique together with interpolation is introduced and studied. With IPC as system platform and PMAC (Programmable Multiple-Axes Controller) as the controlling center of the system, the open architecture of “PC-Based” is used in the CNC system and the framework of the CNC hardware is developed. According to the ideas of modularization and real-time multi-task scheduler, the CNC software system is carved into many modules and the framework of the CNC software is developed.
Research on NC Manufacturing of Slender Helical Curved Surface
Authors: Sun Xing Wei , Cui Hong , Wang Ke , Wang B.
Published: August 2009

Along with the development and advance of science and technology, the quantity demanded of high technology and high performance mechanical equipment, such as screw pump, screw compressor, elastic and plastic extruder, steam turbine, blast engine and turbine, and so on, is great more and more in present society. And the requirement of performance is high more and more. The application of these products is widespread in many major industry fields of national economy, including military, petroleum, machinery, aviation, energy, chemical industry, elastic and plastic industry, etc.. The key part of these products is the rotor with special complex helical curved surface and leaf blade with particular slender curved surface. The machining level of them makes effect on the product performance and quality directly. In this paper, modern manufacturing technology, which makes use of tool nose’s NC trace of revolving disk milling cutter and whirlwind milling cutter to envelope milling slender curved surface by combined moving of several coordinate axes on special NC milling machine, was studied. The principle of the new technique was represented. The application instances are given in this paper.
Axiomatic Design of High Speed Milling Cutter and Fuzzy Object Element Evaluation for Dynamic Cutting Performance
Authors: Jiang Bin , Jiang Ling , Zheng Min Li , Zhou J.
Published: August 2009

According to the theory of axiomatic design, to process function decomposition and grey cluster analysis of high speed milling cutter with indexable inserts, found the design matrix of cutter, and propose the design method of cutter based on high speed milling safety, stability and efficiency. High speed face milling cutter for machining aluminum alloy was developed according to design method and design matrix of cutter, experiment and fuzzy object element evaluation for cutting performance of cutter was accomplished. Results showed that there was not design loop which existed in the development of cutter, design process was simplified effectively, cutting energy of high speed milling cutter using axiomatic design method was dispersed, it held higher safety, cutting stability and efficiency, comprehensive cutting performance met the design requirement of high speed milling cutter.
Study on Intelligent Tool Optimal Selection System in Milling
Authors: Fang Xi Feng , Lan T.X. , Zhang Sheng Wen , Jia W. , Wang Tong Yue
Published: August 2009

Rule-based reasoning (RBR) and weight decision making have been widely used in a lot of decision support systems. According to the waste phenomenon of manufacturing corporations due to the reasonless use of tools during production process, and considering the characteristics of former tool selection systems, develop a tool optimal selection system with Visual Basic 6.0 as development tool and SQL Server 2000 as database developing platform. The system adopts the rule-based reasoning and weight decision-making theory, combines fuzzy theory, artificial intelligent technology and production conditions of corporations. According to the information of workpiece and processing conditions imported by users, the system can select the reasonable tools for users. The system overcomes the limitation of single theory tool selection system, simplifies reasoning mechanism and structure of knowledge base, makes programmer easy to realize, promotes operation efficiency of system, and raises the accuracy and efficiency of tool selection in actual production. A developed prototype system and an example have verified some presented techniques and the research results are the basis of the future development.
A New One-Side Finish Machining Method for Profile of Globoidal Indexing Cam in High Speed
Authors: Tang X.F. , He Wei , Liu Y.S.
Published: August 2009

A new one-side finish machining method for the profile of globoidal indexing cam in high speed, which modifies the tool path of traditional enveloping method, was put forward. The new method is useful for overcoming the defects caused by traditional enveloping method, can realize one-side machining of globoidal indexing cam, can improve the machined surface quality and the meshing characteristics of the cam mechanism. The practical calculation formulas of tool path modification is given, which can be used in developing the CAD/CAM software of the globoidal indexing cam. The new method has great practical value.
An Adaptive Posture Following and Keeping Fixture Based on Aerostatic Bearing and Universal Ball Joint for Aircraft Digital Assembly
Authors: Xiong Rui Bin , Ke Ying Lin , Huang Pu Jin
Published: August 2009

In order to reliably keep and fasten the aligned posture of large components such as fuselage in aircraft digital assembly, a new adaptive posture following and keeping method based on the application of aerostatic bearing and universal ball joint was proposed, and a flexible posture following and keeping fixture was developed. Fundamental experiments of the fixture were conducted, and the results show that the approach can meet the requirement of posture following and keeping. In applications, the fixture can be set multiple-point on the surface of the large component, such as periphery and lower abdomen.