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    10 October 2008, Volume 19 Issue 19
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    Design and Simulation of Multi-step Process for the Automobile Clutch Hub
    Li Xuesong;Chen Jun;Wu Gongming
    2008, 19(19):  0-2272. 
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    According to shape features of the automobile clutch hub under research, an entire process flow was designed, including blanking, deep-drawing, bulging, stamp-cold forging hybrid process, piercing and trimming. The bulging process was designed to form circumferential slots distributing around the clutch hub evenly and the stamp-cold forging hybrid process was designed to gain variable thickness. A particular emphasis was put on introducing bulging process and the hybrid process. FEM simulation software, DEFORM-3D, was employed for the simulation of the entire process. The simulation results demonstrate that the bulging process can form circumferential slots fully and precisely, and the stamping-cold forging hybrid process is successful in forming parts with variable thickness.

    Study on Description of Dynamic Model System for Self-reconfigurable M-Cubes
    Wu Qiuxuan;Liu Shirong;Cao Guangyi
    2008, 19(19):  0-2351. 
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    Self-reconfigurable M-Cubes was analyzed from the sides of module and configuration of system. Exterior states of module were described by eigenvector. Meta-module was utilized to relax the constraint of motion and enhanced the ability of motion for unit module; the states of meta-module were described by eigenvector too. Communication network, energy network and computation network were introduced into static configuration of system. Dynamic graph and cellular automata were introduced to describe dynamically the system configuration. Unit module and configuration were separately described to improve the cognition of system. The simulation shows that the method of description was effective. 

    Robust Variable Structure Control of Spacecraft-referenced End-point 
    Motion of Free-floating Space Robot System with Dual-arms
    Tang Xiaoteng;Chen Li
    2008, 19(19):  0-2272. 
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    The kinematics and dynamics of free-floating space robot system with dual-arms were analyzed, and it is shown that the Jacobian matrix and the dynamics equations of the system are nonlinearly dependent on inertial parameters. In order to overcome this problem, the system was modeled as under-actuated robot system, and the idea of augmentation approach was adopted. It is demonstrated that the dynamics equations of the system can be linearly dependent on a group of inertial parameters. Based on these results, a robust variable structure control scheme for spacecraft-referenced end-point motion of free-floating space robot system with dual-arms with uncertain inertial parameters was proposed, and a planar space robot system with dual arms was simulated to verify the proposed control scheme. The advantage of the scheme is that it requires neither measuring the position, velocity and acceleration of the floating base with respect to the orbit nor controlling the position and attitude angle of the floating base. In addition to this advantage, it is computationally simpler by choosing to make the controller robust to the uncertain inertial parameters rather than explicitly estimating them online.

    Parametric Design Method of Mould Addendum Surfaces for Sheet Metal Forming Simulation
    Chen Tao;Li Guangyao;Sun Guangyong
    2008, 19(19):  0-2354. 
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    The successful application of computer simulation techniques in sheet metal forming raises an urgent requirement for more rapid and automatic die surface modeling method, a new parametric design method of mould addendum surfaces and drawbead was proposed. Using this method, the design of die face was completed in CAE preprocessor instead of in CAD systems as ordinary methods did, and the mold models could be used in sheet forming simulation directly. It makes the design and change of die surface more convenient, and the efficiency of design process is improved greatly. A new method of parametric modeling drawbead in real geometry was proposed. and the position of drawbead can be adjusted easily. Many applications have proved this method is suitable for automotive engineering.

    Nonlinear H∞ Control of Multiple Joint Robot Driven by Ultrasonic Motors
    Sun Zhijun;Xing Rentao;Huang Weiqing
    2008, 19(19):  0-2272. 
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    A three-joint robot was directly driven by ultrasonic motors with advantage of high torque at low speed. On the one hand, ultrasonic motors were driven by the frictional force between rotor and stator, on the other hand, it was almost impossible to identify all the dynamic parameters appearing in the equations of motion of the robot, so there were frictional disturbances and dynamic disturbances due to the parametric uncertainties in the robot control. To solve the problem, a robust nonlinear H∞ control system with the induced L2-gain attenuation was designed. Experimental results show the robot has achieved good positional resolution as well as smooth operation. Finally, a robust experiment shows the controller has a strong performance of anti-disturbances. 

    Study on Fabrication and Their Cutting Performance of High-quality Diamond-coated Tools with Complicated Shape
    Shen Bin;Sun Fanghong;Xue Hongguo;Chen Ming;Zhang Zhiming
    2008, 19(19):  0-2354. 
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    Diamond films were deposited on the WC-Co PCB milling tools with complicated shape surface using electronically aided hot filament chemical vapor deposition (EAHFCVD). During the deposition, the spiral hot filaments arrangement and novel combine pre-treatment method were adopted. SEM and Raman spectrum were employed to study the characterization of as-deposited diamond-coated milling tools. To evaluate their adhesion strength and cutting performance, milling experiments were performed. The experimental results show that the as-deposited diamond-coated milling tools are characterized as high adhesion strength, good wear resistance and excellent cutting performance; and also, low surface roughness can be attained without subsequent polishing processes.

    Kinematics Modeling and Simulation on Tilting and Lifting Mechanism
    Yang Xiuqing,;Mei Tao;Zha Shihong,;Luo Minzhou
    2008, 19(19):  0-2272. 
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    To study the characteristics of tilting and lifting frame’s motion, perfectly make motion planning and realize the intelligent control of hydraulic cylinders, a mathematics model of 7-linkage complicated plane mechanism was built. In order to simplify the problem of intelligent control of hydraulic cylinders the solutions of lifting and tilting of frame were resolved respectively. At first the mathematic model between revolving angle θ of frame and displacement of two hydraulic cylinders was established by two 4-linkage mechanisms, successively on the premise of θ=0 the mathematics model between lifting height Δh of frame and displacement of two hydraulic cylinders was also set up. Later the two mathematics models were figured out by combining with design parameters and using numerical computation method. At last the established mathematics models were proved to be true by comparing the computation result with the result of kinematics simulation.

    Research on Petri Net Disassembly Process Model Based on Constraint Relationship of Parts for Mechanical Equipment
    Li Shiting;Zhu Bo;Cai Qi;Chen Lisheng
    2008, 19(19):  0-2354. 
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    On the basis of analyzing constraint relationship of parts，the characteristics of constraint relationship appled to Petri net model were presented. Constraint relationship of parts was showed by Petri net model, and a disassembly process model was put forward based on constraint relationship. Finally, the action characteristics of Petri net disassembly process model were studied and the validity of model was proved through the example of valve disassembly.

    Optimization for a Deployable Spaceborne Antenna Cablenet Structure 
    with Goals of Surface Accuracy and Natural Frequency
    You Guoqiang;Duan Baoyan;Zheng Fei
    2008, 19(19):  0-2272. 
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    The sequential quadratic programming method was used for the cablenet structure of a deployable spaceborne antenna optimization.Nonlinear finite element method was used to solve the FEM analysis model of the cablenet,and the optimization model was built with the diameter of cables as design variables,surface accuracy of the upper-chord cables and natural frequency of the cablenet as objective functions.Sequential quadratic programming method was used,and optimal Pareto set with different weight values were obtained.Because one of the objective function is the surface accuracy of the upper-chord cables,the cross sectional areas of the cables have a non symmetrical distribution,and it is in accord with a characteristic law.

    Study on the Operation Pattern for Green Manufacturing and Its Case
    Gu Zhenyu;Liu Fei;Li Congbo;Cao Huajun
    2008, 19(19):  0-2354. 
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    Because of lack of systematic description of operation pattern in the existing research on green manufacturing (GM) the meaning of operation pattern for GM was analyzed from the system integration point of view, and then the description of operation pattern was proposed in six views, i.e., objective view, product life cycle (PLC) view, manufacturing processes view, resources view, environment impacts view and composition view.Meanwhile, a four-layer structure GM operation model was built, including goal layer, PLC layer, design and development process layer, supporting systems layer. The applicability and system characteristics of six views architecture was verified according to the well effect of the application case of a machine tool manufacturing enterprise.

    Research on Proliferative Manufacturing Resource Selection Oriented to Process
    Yu Feng;Liao Wenhe;Guo Yu;Su Yan;Gao Shiwen
    2008, 19(19):  0-2272. 
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    To solve the difficulty of outsourcing with low quality and high repair rate in military manufacturing enterprises, which can not satisfy mass orders, the proliferative manufacturing resource selection oriented to process was present. Firstly, based on the matter-element model, quantitative working procedure feature’s matter-element model and proliferative manufacturing resource’s matter-element model were constructed combining with rapid proliferative manufacturing’s specific characteristics. Secondly, through computing dependent function, the matching algorithm was given out. This method was applied in certain military manufacturing enterprise. Finally, an example of proliferative manufacturing resource selection oriented to process was introduced to verify this method.

    Research on Stochastic Processing Time Oriented Job-shop Scheduling
    Yu Xiaoyi;Sun Shudong;Wang Yange
    2008, 19(19):  0-2354. 
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    A job-shop scheduling approach was studied where the processing time was treated as stochastic variables.The individual with highest frequency was
    supposed through all generations,and presented the best
    solution in terms of the fitness function value.Based on this hypothesis,an improved GA to stochastic job-shop scheduling problems(SJSSP) was proposed.A decoding algorithm considering the capacity space of machines was proposed to obtain active-scheduling solutions.Crossover/mutation gene recombining algorithms were introduced to ensure the new individual to meet precedence constraints.The Roulette strategy according to fitness function values was adopted to control the evolution direction of the generation. In addition,an instance shows that the algorithm possesses great validity.

    Research and Implementation of Visual Design and Calculation System Based on Visual Basic(VB)
    Sun Wei;Li Chaofeng;Liu Jie;Wen Bangchun
    2008, 19(19):  0-2272. 
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    The connotation,characteristics,and technical flow of visual design and calculation system were researched synthetically.On the basis of these,a 3-TPT parallel machine tool was taken as study case and the visual design system of kinematics
    was developed by VB.This system can receive the parameters relying on visual interfaces and rapidly realize calculation and simulation of position,velocity and acceleration.Furthermore,the system can also simulate motion status of the parallel machine tool utilized bitmap animation.Practice indicates that opening visual design system is an effective measure to make research results be applied fast in the engineering practical design.

    A Fast Algorithm of Circle Detection for Industrial CT Images Based on Probability of Existence
    Liu Fenglin;Qiao Guifeng
    2008, 19(19):  0-2354. 
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    The circle structure widely exists in the Industrial CT images. It is significant to detect the circle, obtain the parameter and apply to the image measurement as well as the reverse engineering. To overcome the defect of long-time calculation and memory consuming in the current method of existence probability map for detecting circles, the present study first made sure the potential range of the center of circle, and stored the message which met the required numerical values in the chain and then decided the parameter of circle and marked the position according to the checked number. The research will reduce calculation task and save the internal stored capacity while using the form of chain. The result shows that this method has improved greatly the calculation rate 36~178 times than that of the original one.

    Research on the Technology of Dynamic Knowledge Relating and 
    Navigation Oriented to the Process of Product Development
    Chen Jing;Zhang Shuyou;Yi Guodong
    2008, 19(19):  0-2272. 
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    In order to implement the knowledge supporting for the process of product design, and enhance the efficiency and the quality of the product development, a method for knowledge relating and navigation which oriented to the process of product development was put forward. The static description for knowledge extended to the dynamic field, at the same time knowledge drive factor was established, by the dynamic relationship between knowledge and the process of product development, the knowledge navigation of product development was implemented. The plant of the process of product development-oriented knowledge management was constructed, meanwhile the plant was applied in the process of low voltage apparatus product development successfully.

    Study and Development of a Virtual Assembly System Based on Division Mockup for Satellite
    Xia Pingjun;Yao Yingxue;Sun Gang;Yi Wangmin
    2008, 19(19):  0-2354. 
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    Based on Division Mockup, the architecture of a virtual assembly system for satellite was proposed, and the assembly process planning and simulation were finished. Aiming at the shortcomings of only concentrating on assembly simulation for Division Mockup, an assembly process generation system was developed, which can be integrated with Division Mockup by a data interface, so the assembly steps planning, assembly documents generation and assembly training can be achieved. At last the application examples were given.

    Research on Stereo Matching for Monotone Texture in Photogrammetry
    Yan Long;Zhao Zhengxu;Zhou Yiqi
    2008, 19(19):  0-2272. 
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    This article set the constraints for stereo match and searching scope by edge detecting, epipolar geometry and correlation of stereo pairs, then got the matching result by iterative area match with coarse to fine strategy. Experiments prove that this algorithm promotes matching accuracy,and eliminates influences of monotone texture. The result data proves suitable for 3D reconstruction in reverse engineering.

    Study on Four-quadrant Optoelectronic Detector in Surface Topography Measurement
    Wang Shuzhen;Xie Tiebang;Chang Suping;Wang Xuanze
    2008, 19(19):  0-2354. 
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    A spatial arrangement of four-quadrant optoelectronic detector was presented to detect interference fringes in 3D surface topography measurement. The relationship among fringe width d, rotary angle β with amplitude, phase difference of difference signal of optoelectronic detector was analyzed by integral analysis under ideal conditions. The value of appropriate fringe width d and according rotary angle β that meets orthogonality relation were given. A pre-amplifer circuit of PIN four-quadrant photodiode arrays was designed for 3D surface topography measurement. The experimental analysis indicates that the two difference signals satisfy the requirement of counter and subdivision and the spatial arrangement of the PIN photodiodes reaches the accuracy of nanometric level measurement.

    Nondestructive Evaluation of Adhesive Interfaces in MMCS Using Nonlinear Ultrasonic Method
    Dun Yi;Shi Xiaohong;Xu Zhangsui
    2008, 19(19):  0-2272. 
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    This paper presented a nonlinear ultrasonic approach for evaluating adhesive bond quality of a test metal matrix composite structure (MMCS) specimen interface. The acoustic compression waves can be used to detect void debond at adhesive interfaces. However, it remained a largely unanswered challenge to obtain information on adhesive bond strength from ultrasonic test results. It is possible that using nonlinear acoustic techniques to measure properties of adhesive interface in MMCS. The basic parameter that has to be evaluated is the so-called nonlinear coefficient β. The differences of nonlinear coefficient indicate local variations in adhesive quality. With further work it is hoped to demonstrate that the nonlinear coefficients will be used to evaluate the quality of MMCS bond interface.

    Optimization Design for Kinematic Accuracy Reliability of Shaping Mechanism
    under Incomplete Probability Information
    Zhang Yimin;Huang Xianzhen;Zhang Xufang;Lü Chunmei
    2008, 19(19):  0-2354. 
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    The optimization design for kinematic accuracy reliability of shaping mechanism under incomplete probability information is extensively discussed in this paper by combining the reliability theory and optimization technology, and a numerical method for reliability-based optimization design is proposed. Under the condition that the first four moments of basic random parameters are available, computer programs based on this model can complete the reliability-based optimization design for kinematic accuracy of shaping mechanism, and acquire the design information accurately and quickly.

    Response to Harmonic Voltage Excitation for Electrostatic Harmonic Micromotor
    Qin Lei;Xu Lizhong
    2008, 19(19):  0-2272. 
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    A novel harmonic micromotor actuated by electrostatic force was proposed, whose basic operating principles were also described. The static and dynamic components of the electrostatic force and load due to the harmonic voltage excitation were derived for the micromotor. Displacement distribution for forced vibration was formulated as a series form of the mode shapes for free vibration. Furthermore, the governing differential equations based on the Donnell’s shell theory were simplified. In virtue of the orthogonality of shell modes, the dynamic response to harmonic voltage excitation was determined and its variation was summarized. Finally, resonance characteristic was analyzed for the system subjected to harmonic excitation. Its changes along with the main system parameters were also given.

    Efeects of Magnetic Pole Arrangement on Magnetic Field and Force in Radial Magnetic Bearings
    Ding Guoping;Hu Yefa;Zhou Zude
    2008, 19(19):  0-2354. 
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    Magnetic field of an 8-pole radial magnetic bearing was modeled through finite element method (FEM) and the magnetic flux lines were presented. The air gap magnetic flux density and magnetic forces with different rotor eccentricity were calculated and compared under NSNS alternating arrangement and NNSS paired arrangement. The magnetic bearing’s magnetic field model and calculation were verified with measurements. Results show that air gap magnetic flux density and magnetic force of NSNS arrangement are greater than the ones of NNSS arrangement with same input currents. So the NSNS arrangement always gives smaller magnetic bearings. However, it is with stronger magnetic field coupling between adjacent pole pairs of NSNS arrangement than that of NNSS arrangement, NSNS arrangement will result in more complicated coil current control. It is significative to use the conclusion of this paper in magnetic bearing design.

    Design and Simulation of Rod Transmission with Harmonic Planetary of Low-speed Motor
    Yang Xiaolan
    2008, 19(19):  0-2272. 
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    The combination of harmonic planetary transmission and rolling
    cam transmission was proposed and named by rod transmission with harmonic planetary,which made radial movement of follower take the place of elastic-deformation of soft wheel in harmonic transmission.By kinematic simulation of Pro/E and dynamics simulation of ADAMS software,the low-speed motor of DGX180-1 and DGX180-2 can be gotten separately，which was powered by rod harmonic.The simulation resalts state that the manufacturing cost made by rod harmonic transmission can save as much as 40% compared with the general harmonic transmission by using the same power.Rod harmonic transmission
    realized optimization by design of experiment(DOE) simulation of ADAMS and kinematic simulation of Pro/E.Follower rod length cuts down 45%,radial dimension of the drive part reduces 23%,weight lightens 18%.The results indicate that this low-speed motor in rod transmission of harmonic planetary will have a widely application prospects in the market.

    Study on Nonlinear Dynamic Behaviors of Mechanism with Links Fabricated from Symmetric Laminates
    Cai Ganwei;Li Zhaojun;Zhu Tianyan;Dai Wenzheng
    2008, 19(19):  0-2354. 
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    The work was concerned with nonlinear dynamic behaviors of linkage mechanisms with links fabricated from symmetric laminates.A group of dynamic nonlinear equations of the linkage mechanisms were established by the finite element methods,where the geometric nonlinearity of flexible component was considered.The nonlinear dynamic behaviors of the mechanisms were analyzed by the method of multiple scales.
    Simulation of time-domain and frequency-domain dynamic response characteristics curves of the links were obtained when the mechanisms satisfied the conditions of inner resonance and super-harmonic resonance.The results show that the natural frequencies and dynamic responses of the mechanisms are related to the material parameters of symmetric laminates and that the characteristics of the mechanisms may be improved by adjusting the material parameters.

    Intelligent Fixture Planning Based on Artificial Neural Network and Genetic Algorithms
    Zheng Junhong;Ye Xiuzi;Chen Zhiyang
    2008, 19(19):  0-2272. 
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    This paper presented an algorithm of fixturing surfaces grouping and selection based on Kohonen self-organizing neural network and the algorithm of optimizing locating points based on genetic algorithm. Artificial neural network was utilized to deal with the complicated influencing factors in fixturing surface selection to select the best fixturing surfaces. Based on the results of fixture verification, the stiffness and deformation of the workpiece was simulated. Genetic algorithm was then adopted to optimize the combination of locating points. Examples were presented to validate the algorithms.

    Experimental Investigation of the Dynamic Behavior of Hardened Steel
    in High Strain Rate and Parameter Fitting of Constitutive Equation
    Lu Shihong;He Ning
    2008, 19(19):  0-2354. 
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    To determine the true flow stress-true strain relationship for H13 hardened steel, specimens were first tested from a strain-rate of 1000s-1 to 10 000s-1 and from room temperature to 600℃ at intervals of 200℃ with a split Hopkinson pressure bar apparatus in the solid mechanics laboratory of Northwestern Polytechnic University. The results show that the flow stress is influenced by both strain rate and deformation temperature, and the flow stress decreases with the increase of temperature. The parameters for a Johnson-Cook constitutive equation were determined from the test results. The comparison between data of experimental and fitted constitutive equation indicates that the constitutive equation is suitable for expressing the dynamic behavior of H13 steel, which provides important material characteristic parameter for mechanics numerical analysis further in the project application. 

    Microstructure of WC Matrix Tool Composites and Its Failure Mechanism
    Yang Fazhan;Zhao Jun;Ai Xing;Zhou Jianqiang
    2008, 19(19):  0-2272. 
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    The microstructure, fracture mode and crack propagation of WC matrix composite was analyzed by SEM and TEM. Experimental results show that the fracture mode is mainly of transgranular due to the addition of nano size zirconia and alumina particles. TEM pictures reveal that some small zirconia particles are uniformly located within WC matrix grains and some large zirconia particles are distributed between WC and Al2O3 grains. In WC matrix composite, the addition of zirconia influences the shape of WC grains. The interfaces of WC-ZrO2, WC-Al2O3 and Al2O3-ZrO2 in the composite were also studied by TEM, and fewer pores were detected. The cutting performance of the new tools was studied by machining titanium alloys (Ti6Al4V) and the wear and fracture mechanism was analyzed and the results show that adhesion and fatigue wear are the main failure mode.

    Wear Behaviors of MoSi2 at Different Elevated Temperature
    Zhang Houan;Li Pengnan;Hu Xiaopin,;Chen Tengfei
    2008, 19(19):  0-2354. 
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    The tribological properties of molybdenum dislicide (MoSi2) against Al2O3 in the range of 700~1100℃ were investigated by using an XP-5 type high temperature friction and wear tester. Microphotographs and phase status of the worn surface of MoSi2 were observed by SEM with EDS and X-ray. Results show that friction coefficient of MoSi2/Al2O3 sliding friction couple increases with the increase of temperature when it is less than 900℃ and MoSi2 has low wear rate. The main wear mechanism of MoSi2 are adhesion and oxidation. However over 900℃, friction coefficient keeps in the range of 0.6～0.8 although it decreases a little with increasing temperature, and wear rate of MoSi2 is clearly raised. This is that because of the ductile - brittle transition characteristic of MoSi2, abrasion, plastic deformation and fracture are also found on the worn surface of MoSi2. Adhesion is the main wear mechanism of Al2O3

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