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Table of Content

    25 June 2012, Volume 23 Issue 12
    Contour Error Analysis for Rotation Feed Axis in CNC Machines
    XIE Dong-1, 2, DING Jie-Xiong-1, HE Pan-Bei-1, DU Li-1, WANG Wei-1
    2012, 23(12):  1387-1392. 
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    As one axis of five-axis CNC machines,rotary axis servo system dynamic performance impacts heavier on the contour accuracy than that of  linear axes and has to be treated carefully.Herein,the servo system model of axis rotation was established firstly.The rotation axis commands were formed based on the conversion system from the tool position to processing system,the output instructions were related to the servo system dynamic error model,and then the output instructions from the processing system were converted back to the tool position system.The deviation was given from comparing the position of the tool with the designing surface and the contour errors were shown. A series of points on the contour were selected to calculate the errors from the joint motion of rotation axis in the five-axis CNC machine.The relation between the points with biggest departure and the geometric characteristics were analyzed. It may be used to evaluate the dynamic errors from rotation axis rapidly for adjustment
    and maintenance of CNC machines.

    Decoupling Mechanism of  EDF Based on Design Priority Evaluation
    ZHOU Dan-1, LIU Guang-Bi-1, HE Beng-1, 2
    2012, 23(12):  1393-1399. 
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    The EDF connecting the product's design information and its energy characteristics was difficult to convert to design parameters and control measures,which was coupled with large amount of design elements.Aiming to solve this problem,the decoupling mechanism of  EDF was built.The decoupling mechanism was constituted by analyzing coupling characteristics,constructing coupling element relation matrix(CERM),evaluating design priority of coupled element and gaining energy design parameters and
    optimum value(or control measures and target).In addition,the max cut width bDlim of  NC machines was selected as an illustrative example to show the decoupling mechanism of EDF.

    Study on Dynamics of Micro Gas Journal Bearing-rotor System
    ZHANG Hai-Jun-1, CHU Chang-Sheng-2
    2012, 23(12):  1400-1403. 
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    According to 1_st order slip velocity boundary,a modified Reynolds equation for micro gas bearings was derived. Alternating-direction implication method was adopted to solve modified Reynolds equation and nonlinear gas film force was calculated. With the motion equation of rigid rotor, the unbalance response of the rotor system was computed and the trajectory of rotor center, time history, power spectrum and Poincare maps were calculated and the dynamics of micro gas bearing-rotor system was analyzed. The analysis shows the existence of a complex dynamic behavior comprising periodic and subharmonic response of the rotor center. 

    Construction Technology of Cooling Channel Based on Adaptive Growth Method
    YANG Dong-Sheng, DING Xiao-Gong, JI Hua-Rong, LIU Wei
    2012, 23(12):  1404-1407,1432. 
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    The adaptive growth method based on the growth mechanism of branch systems morphologies in nature was applied to solve volume-point problem.The thermal conductivity of each element was selected to be as design variable and minimization of the maximum temperature in the design area was the objective.The material with high thermal conductivity was distributed gradually to the design area and the adaptive growth of cooling channel was realized.Several typical volume-point problems were analyzed and compared with the results of current methods.It is found that the adaptive growth method can be used to construct cooling channel effectively. 

    Research on Reliability Prediction for Roller-slide Based on Brownian Motion with Drift
    CA Jing, LIN Chu-Gong, LIU Xiao-Hua
    2012, 23(12):  1408-1412. 
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    Because the roller-slide has the characteristic of high wearability and few failure data,the reliability of the roller-slide was researched using the performance degradation theory and stochastic process methods.On the basis of analyzing the wearing process of the roller-slide,a reliability model based on Brownian motion with drift was built,and then the residual life prediction method based on current wear quantity
    was developed with the characteristics of Brownian motion.Finally,an example was given to show that the proposed method is validity and the prediction accuracy is acceptable.Also,the method provides a foundation for maintenance decision.

    A Method of Compiling Load Spectrum on Wheel Loader Transmission
    LIU Yong-Chen, CHANG Lu, SUN Li
    2012, 23(12):  1412-1416. 
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    In order to guide the reliability design on the wheel loaders,a method of compiling load spectrum on wheel loader transmission was proposed.Load signals of the wheel loader transmission were tested by using five-fragment method.The load signal frequency characteristics are less than 1Hz by frequency spectrum analysis.Accordance with the four fragments of  “empty load,shovel load,full load and unload” cycling characteristics,the load signals were processed smoothly by splitting and merging them.Through the rain-flow counting,it is concluded that mean load is fit to the normal distribution and load amplitude is fit to the Weibull distribution.And by synthesis conditions,the statistical extreme value of load amplitude was inferred.By using the wave center method,the eight load spectrum and the program load spectrum of the wheel loaders transmission parts were
    compiled.It is concluded that wheel loader transmission load signals can be dealt
    with four paragraphs smoothly according to significant characteristics,and probability
    distribution characteristics are clear.The load spectrum is consistent with
    loader real work conditions.

    Study on Flow Field in Hydrodynamic Suspension Machining with Deflector
    JI Shi-Ming, HE Jian-Min, HONG,TAO,WU Jia-Feng
    2012, 23(12):  1417-1422. 
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    In order to improve the low processing efficiency in hydrodynamic suspension machining, a method was proposed, which was based on a deflector module that can alter the flow field in hydrodynamic suspension machining. The dynamic model of hydrodynamic suspension machining with deflector was established,which was based on theory of hydrodynamic pressure and realizable k-ε turbulent model. The value of hydrodynamic pressure and speed are both larger than hydrodynamic suspension machining without deflector and are increased 5.04% and 1% respectively. The pressure and velocity willbe generated to a peak in the minimum clearance region and can be increased by rotation speed. The experimental results show that the roughness of workpieces surface drops to 0.018μm under the speed of 6500r/min after 90 minutes polishing and gets a relatively ideal processing effect.

    Research on Structure and Driving Principles of Inchworm-like Bionic Micro-robot
    LI Yu-Feng, SUN Hong-Qing, CHAN Pan-Xia
    2012, 23(12):  1423-1427. 
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    A new bias two-stroke SMA micro-driver was put forward,a four-legged bionic micro-robot which moved like an inchworm was designed in the foundation of the actuator.A new bionic foot based
    on a four-linkage mechanism was advanced,the output force direction of the micro-driver was changed by using the new feet.The friction self-locking principle of the new feet
    was analyzed and conditions for friction self-locking of the new micro-feet was
    obtained,the forward movement of the micro-robot was achieved reliably.The driving principle of inchworm bionic-robot was expounded.The motion regular and step and frequency
    of inchworm-robot were analyzed.

    A Global Calibration Method for Multisensor Metrology System
    MAO Lu-Xi, YIN Zhou-Beng, XIONG Wei-Lun
    2012, 23(12):  1428-1432. 
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    Focusing on multisensor metrology system consisting of trigger and arm laser scanner in a complex surface part manufacturing process,a global calibration method was proposed based on hexahedron.The global calibration mathematical model based on unit quaternion method was constructed.Aiming to determine the optimal rigid transformation matrix,mathematical morphology was applied to cluster analysis on unit quaternion sphere.The simulation and industrial examples demonstrate this method is convenient,accurate and be fit for on machine metrology system calibration.

    Study on Clutch Engagement Process Dynamics Characteristics for  Deep Drilling Rig
    WU Yi-Wen, BO Chang-Gen
    2012, 23(12):  1433-1437. 
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    The purpose of this paper was to study the clutch engagement process dynamics for deep core drilling rig,a dynamics model for clutch engagement process was built up and MATLAB programming was used to solve differential rotating equations.Clutch manipulation,gear and drilling depth will affect engagement time,slipping power,and friction work.It is shown that the deeper the drilling hole,the longer the clutch engagement time.As the drilling depth increases,the friction work increases
    linearly.Gear transmission ratio will affects the moment of inertia and the moment of mud damping force and bit cutting surface resistance greatly.For a specific rig it can start in second gear within 500m. 

    Research on Information Integration Framework of SysML Based Model-driven Design of Complex Products
    LIU Yu-Sheng, YUAN Wen-Jiang, FAN Gong-Ri, CAO Yue
    2012, 23(12):  1438-1445. 
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    Aimming to build the association among different levels of design information and simulation information of different physical domains of the complex mechatronic products, a SysML-based framework of an integration of hierarchical design and simulation information was proposed for supporting the model-driven design of multi-domain complex mechatronic systems. An integration information model was established based on the extension mechanism of stereotype of SysML. After that, the meta-models of SysML and Simscape, a typical simulation modeling language, were explored and the mapping rules between them were also studied. The integration method between the system-level design and simulation information was proposed based on triangular graph grammar(TGG). At last, some examples were shown to illustrate the proposed method and some discussion was also given.

    Application of ABC Algorithm in Identification and Control of Nonlinear Systems
    ZHOU Hai-Feng, WANG Rong-Jie
    2012, 23(12):  1446-1451. 
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    The problem of nonlinear system identification and design of its controller were considered herein.Firstly,a new ABC optimization algorithm was introduced,which generated the initial value of optimization parameters using chaotic maps.Then the proposed algorithm was applied to estimate parameters and to design PID controller.The simulation results of nonlinear systems show that the proposed algorithm can get better convergent and identification performance than other optimization algorithms.The simulation results also show the automatic voltage regulator system can improve dynamic respond behavior using chaotic ABC algorithm PID controller,and its superior performances to other conventional methods.

    Mathematical Models and Finite Element Analysis of a New Type Gear
    LI Hai-Xiang, CHEN Bing-Kui, TAN Ru-Long
    2012, 23(12):  1451-1455. 
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    A new tooth profile gear, “S” tooth profile gear, was proposed herein. The mathematical models, including the equation of tooth profile curve and equation of tooth surface, were established based on kinematical method of meshing theory. A finite element model was established and the finite element analysis in the condition of contact was finished by UnigraphicsNX, Hypermesh and ANSYS software. The results illustrate that “S” tooth profile gear have the advantages of bearing of greater loading force, etc.

    Research on PCB Collision Based on ABAQUS/Explicit Dynamic
    LIU Zhi-Feng, ZHANG Jing-Dong, CHENG Huan-Bei
    2012, 23(12):  1456-1461. 
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    The theories of central difference arithmetic,stable time'slimit and the theory of energy balance were analyzed systematically,the impact of stable time's limit and energy balance due to
    mechanical parameters of materials such as stiffness,density and mesh
    density was researched.Then a finite element model was built and the method of
    Wheatstone bridge was used to validate model's accuracy.Finally,a detail research on PCB collision was made based on the experiments and simulation,it indicates
    that ABAQUS/Explicit can deal with the impact load precisely.The calculation cost will be reduced and the precision will be satisfied as well by applying the theory of energy balance,the strength of the packaging meets the reliability requirements of PCB.

    Parametric Vibration Analysis and Control in Coupling Rotating Mechanical Drive System
    LIU Shuang, LI Yan-Shu, LIU Ban, LI Hai-Bin
    2012, 23(12):  1461-1466. 
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    Taking the torsional vibration of a kind of rotating machanical
    drive system as the research object,considering the influences of time-varying stiffness and nonlinear friction damping,a coupled nonlinear dynamic equation of rotating mechanical drive system was obtained on the basis of Lagrange theory.The average equation of
    system was deduced with the aid of method of multiple scales.Besides,according to Hopf bifurcation theory the necessary and sufficient conditions of Hopf bifurcation and the judgment method of periodic motion's stability were given,and the bifurcation characteristics of system were analyzed under the condition of parametric resonance and internal resonance.In order to suppress instability oscillation of drive system caused by subcritical Hopf bifurcation, a nonlinear feedback control was introduced.After including the controller,the Hopf bifurcation points of system can be transferred,
    and the stability and amplitude of limit cycle were controlled.Through above study,
    an effective method was provided for parametric vibration ananlysis and control in nonlinear rotating machineries.

    Experimental Study on Hydrodynamic Performance of Inclination-dimpled Surfaces in Gas Lubrication
    BAI Lin-Qing-Ma-Yuan-Yuan, BAI Shao-Xian, MENG Xiang-Kai, BANG Xu-Dong
    2012, 23(12):  1467-1469,1474. 
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    In order to investigate influence of distribution type on hydrodynamic performance of gas lubricated inclination-dimpled surfaces,experiments were carried out herein.Surfaces of three typical distribution types,part-textured,full-textured and double-row-textured,were investigated,and film thickness and friction torque were measured during testing.Results show that,the coupling faces can separate quickly with increasing rotation speed.Another important result is that the part-textured surface has larger hydrodynamic effect than that of the full-textured while the double-row-inclination-dimpled surfaces has the strongest hydrodynamic open force.The hydrodynamic effect increases with increases of  rotation speed.The experimental results agree well with theoretical analysis,which provides experimental dependence for design of micro-pored surfaces.

    Error Modeling and Sensitivity Analysis of Spherical 5R Parallel Manipulator Based on D-H Matrix
    LI Yong-Quan, ZHANG Li-Jie, GUO Zhi-Min, GUO Fei
    2012, 23(12):  1470-1474. 
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    Based on D-H transformation matrix,an error model of spherical 5R parallel manipulator was established firstly by virtue of loop circuit incremental method.Here,mechanical structural parameter errors
    were considered,at the same time,considering the deviations among axes of  each revolute joint
    and centers of sphere from the reason of processing and assembling etc.
    These made the error models more close to actual projects.Secondly,the explicit function relationship among all follower movement parameter errors and axis-direction clearance quantity was obtained according to the error model.Finally,sensitivity of the manipulator was analyzed,contribution of each geometrical error component to the kinematics accuracy of the manipulator was researched.This lays a theoretical foundation for calibration,kinematics compensation and applications of the prototype.

    Design and Kinematic Characteristics Analysis on Space Cam-helix Deployable Mechanism of Folding Missile Wing 
    HU Meng, LI De-Bei, CHEN Wen-Hua, ZHANG Miao-Miao, JIAN Ping
    2012, 23(12):  1475-1478. 
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    A new kind of space cam-helix deployable mechanism of missile folding wing was provided herein,and then its working principles
    and technical parameters were determined.Based on analytical method and reversal theory,its motion law,cam profile curve,its pressure angle and radius of profile curve on the space cam mechanism of folding wings were designed.Theoretical modeling of deploying
    kinematics were made and solved.Results show that the deployable mechanism of missile folding wing meets the design requirements and its motion law design of the folding wing is correct.

    Study on Abnormal Phenomena of Radial and Axial Thermal Deformation of Cylindrical Parts
    LUO Zai, LIU Yi, GUO Bin, FAN Wei-Jun
    2012, 23(12):  1479-1481. 
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    A phenomenon was found by experimental results that the same size of cylindrical parts had different radial and axial thermal deformations under the same conditions. And the traditional therodynamic theory could not explain this phenomenon. The relationship between volume expansion coefficient and linear expansion coefficient of crystal was built up by using the Lattice vibration theory of solid-state physics. Based on this relationship, a radial thermal deformation of cylindrical model was set up. The model was different with the traditional model. The experimental results show that the value which calculated by the model is closer to the experimental results than that by the traditional model, and cylindrical parts have different radial and axial thermal expansion coefficient. Traditional model of axial thermal deformation can not be used in micro-field when calculating the radial thermal deformation of cylindrical parts.

    Research on White-light Interferometer Automatic Scanning Technology Based on Threshold
    TUN Zhi-Shun, CUI Chang-Cai, XIE Rui-Fang, HUANG Hui, LI Bing, HUANG Chun-Ji
    2012, 23(12):  1482-1486. 
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    In order to overcome the inefficiency and low precision of manual search for interference fringes and the difficulty of determining interference scanning range, a new kind of automatic scanning technology was put forwarded. It could realize auto-focus, and it can also determine the interference scanning range of the white-light interferometer. The technology, based on the image gray variance change included the following steps: first, computing the image gray variance change ratio; second, comparing this ratio with the predetermined threshold,then judging the initial and ending positions of the interference fringes; and finally, determining the interference scanning range according to the two positions. Experiments show that,when the threshold of the used method is set as 0.5, the interferometer which has coarse and fine double level of driving structure can complete automatically scanning process of the height of 1.2μm in three minutes accurately, two times faster than manual adjustment.This technique can improve the efficiency and automation level of the white-light interferometer.

    Resource Service Chain Construction for Networked Manufacturing Based on FAHP and Improved Ant Colony Algorithm
    WANG Zheng-Cheng, XIE Xian-Wen
    2012, 23(12):  1487-1492. 
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    The nature of networked manufacturing resource integration
    and optimized configuration is a complex process.In this process, total collaborative
    manufacturing tasks can be decomposed to construct a single-task-driven chain according to time and sequence constraints in cross-organizational.The process mainly
     included three stages:the decomposition of the collaborative manufacturing tasks;
    the evaluation and selection of the manufacturing resources and the construction of the single-task-driven manufacturing resource chain.Firstly,according to the
    features of the collaborative task decomposition,a process model for cross-organizational collaborative manufacturing and corresponding decomposition algorithm were proposed.
    Secondly it also put forward an index system and evaluation algorithm for
    the networked manufacturing resources evaluation.Then the networked manufacturing
    resource service chain model and the algorithm which was based on improved ant
    colony algorithm with single task-driven related timing constrains were proposed.
    Finally,a simulation was taken to verify the feasibility of this research.

    Pulse Current Discharge for Strengthening Welded Joints of  Dissimilar Steel and Analysis of Mechanical Properties
    ZHENG Li-Juan, XIANG Long, LIU Hui-Ying, LI Hui, FU Yu-Meng
    2012, 23(12):  1492-1495. 
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    Strengthening welded joints of dissimilar materials
    was studied based on electromagnetic heating crack arrest.
    Through the numerical simulation method the welded joints with embedding elliptical
    crack were discharged,the thermal stress field was obtained and the residual stress was also obtained via cooling to room temperature.The simulation results show that at the time of pulse current discharge in welded joints with crack the temperature at the place of crack tip is beyond its melting point,meanwhile the crack tip blunts and generates compressive stress which is good for workpiece.Through studying the electromagnetic heating crack arrest
    experiments for welded joint of Q235 and 1Cr18Ni9,it proves that when specimen is discharged the mechanical property of welded joints will be better than before,the tensile strength is improved by 19.4% and the impact toughness is improved by 12.07%.

    Research on SBW System's Control Method Based on SDRE Technique
    CHEN Xin-1, 2, ZHANG Gui-Xiang-1
    2012, 23(12):  1496-1501. 
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    This paper studied the controller of a SBW system via a SDRE technique.Based on the vehicle dynamics and the tire model,the state dependent coefficient(SDC) form of  the SBW was established.Since the dynamic equations were highly non-linear,the controller was designed with a SDRE technique.
    Finally,the controller was solved using θ-D method because it had outstanding computing efficiency and sufficient control accuracy.The simulation results show that the SDRE
    method has better tracking precision and improves steering stability and reduces motor energy consumption.

    Accurate Calculation of Tooth Surface Deviation Based on Automobile Driving Axle Hypoid Gear
    DENG Xiao-Zhong-1, LI Tian-Xin-1, 2, LI Ju-Bei-3, ZHOU An-Cai-4
    2012, 23(12):  1502-1508. 
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    In order to obtain accurately the deviation of  the
    actual machined tooth surface and improve effectively the tooth surface
    precision for the automobile driving axle gear,the kinematic relations of  the
    NC machining and the digital measurement were deeply analyzed by combining the superiority in gear transmission of automobile driving axle gear and
    the particularity in the machine tool adjustment,the machining method and
    the tooth surface detection so on.By means of the complexity of topological
    structure of tooth surface of the automobile driving axle gear and the calculation principles of tooth surface deviation,an accurate calculation method was
    put forward to determine the real tooth surface deviation of automobile driving axle gear on the basis of the measurement data of the actual tooth surface.
    Finally,the correctness and effectiveness of the accurate calculation method of tooth surface deviation was verified by the comparisons of the machining and measuring results.

    Research on Residual Stress Measurement of Railway Wheel
    DING Chao, WANG An-Ke
    2012, 23(12):  1508-1511. 
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    With the help of simulation analysis method,the change laws of saw kerf width and stress/strain near the kerf  were studied when radial saw cutting.
    The analyses show that when the saw cutting depth reaches the joint of
    rim and plate, the release of residual stress is sufficient enough to calculate the residual
    stress on the tread based on release information of residual stress.On the basis of the radial saw cutting method,strain gauges were pasted near the kerf and record the strain change when saw cutting. The residual stress was calculated according to the strain change information.