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Table of Content

    10 August 2009, Volume 20 Issue 15
    Topology Optimization of Full-stressed Structures Based on SKO Method
    Ding Xiaohong;Cheng Li 
    2009, 20(15):  0-1770. 
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    All of biologic structures in nature are perfectly optimum structures under the control of their adaptive growing rules in which neither over-loaded nor non-loaded areas exist. The SKO method that is on the basis of the similar adaptive growing rules can be applied to the structural topology optimization to obtain the optimum layout of material in engineering structures. The full stress axiom was used as the SKO design criteria, and the implementation approach of SKO method was studied. Moreover, the design strategies and parameters were discussed in detail. Some typical examples were studied to demonstrate the validity of the suggested proposal.

    Research on 3D Cutter Radius Compensation for 5-Axis End Milling
    Hong Haitao,;Yu Dong,;Zhang Lixian,;HanLi,
    2009, 20(15):  0-1889. 
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    In order to deal with the problem of 3D cutter radius compensation for 5-axis end milling, the calculation method of compensation vectors with several cutting tools was deeply studied based on UG,a CAM software. A private post-process program for 5-axis machine with dual rotary tables was developed,which can output the G-CODE with compensation vectors. Finally, the compensation processing algorithms is verified to satisfy the requirements through the simulation software VERICUT and actual processing.

    Design and Implementation for Metal Micro-droplet Generation System
    Jiang Xiaoshan;Qi Lehua;Luo Jun;Zeng Xianghui;Yang Fang
    2009, 20(15):  0-1770. 
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    Droplet generation is a random process during the micro-droplet deposition manufacture. In order to regulate the droplet generation, key parameters of the field were sampled and feedback controlled to build a closed-loop system for the metal micro-droplet generation. The system was developed with the modular architecture and the key parameters were controlled effectively according to the virtual instrument technology.Experimental results show that the size and shape accuracy of micro-droplet are improved by regulating the disturbance frequency. Under the condition of optimal disturbance frequency, the narrow-sized metal droplet is produced. The relative deviation of droplet diameter is less than 3%, which meets the requirements of manufacture. These works are useful for further study on the fabrication of minimized metal part.

    Research on Synchronous Control for Earthquake Simulation Platform Hydraulic System
    Jiang Xiaoxia
    2009, 20(15):  0-1889. 
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    Based on the hydraulic system of earthquake simulation platform, the paper proposed a nonlinear compensation approach for three directions to six hydraulic cylinder system.The proportion of different non-linear compensation were set by step control, so that up-and-down movement of earthquake simulation platform was coordinate. A double closed loops system composing of position errors and velocity errors was employed to turn the PID parameters adaptively. The steady errors caused by the leakage and dead-zone of the hydraulic cylinder can be compensated by zero compensation method. In addition, using the forecasting module,the value of compensation was adjusted automatically and expediently. 

    Hybrid-Solving Methods of Engineering Equipment Scheme Design Based on RBR and KBG
    Peng Weiping;Wei Yanhong;Wu Qinming
    2009, 20(15):  0-1770. 
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    To improve the capacity and efficiency of the design system of backup transportation scheme for tunnel boring machine(TBM), a new hybrid-solving method was proposed. The practical goal of this research was to bring rule-based reasouing(RBR) and knowledge-based guiding (KBG) together.Metarule was used to manage rule-design and control process-solving and migrate KBG node-workflow based on object message mode.A more effective human-computer collaboration and interaction technique was provided for complex engineering equipment scheme design under the lack of rule-design integrity and the difficulty to find cases.

    Trajectory Planning and Simulation Confirmation for a Planar Parallel Framework
    Yang Xiuqing,;Mei Tao;Luo Minzhou;Wang Hailian
    2009, 20(15):  0-1889. 
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    A new method of trajectory planning was proposed by analyzing the complicated geometry relationship of a planar parallel framework and combining the modeling and simulation technology of virtual prototyping. This method can implement the accurate trajectory planning of driving joint by converse simulation. The kinematics converse solution of system was avoided by this method, so some shortcomings of the traditional planning method such as non-unique of the kinematics converse solution, the great computation, the bad real time and so on were conquered, moreover the continuity of displacement, velocity and acceleration of the end trajectory and each joint was guaranteed. At last the validity and accuracy of this new method was confirmed by the kinematics simulation of system.

    Analysis of Isolation of the Torsional Vibration of DMF-CS with 
    Centrifugal Pendulum-type Absorber
    Li Wei,;Long Yan;Shi Wenku
    2009, 20(15):  0-1770. 
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    The differential equations of DMF-CS with pendulum-type absorber were established, the natural frequency of pendulum was computed, and the characteristics that the frequency was proportional with the rotate speed of the flywheel where the pendulum was installed was found. Using this characteristic, the vibration of engine fire frequency will be absolutely eliminated theoretically by adjusting the parameters of the centrifugal pendulum.The influencing factors of performance of vibration isolation were analyzed.

    Geometric Error Measurement of Spiral Bevel Gears and Experimental Test
    Cao Xuemei;Wang Jun;Zhang Haiying
    2009, 20(15):  0-1889. 
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    This paper calculated the theoretical tooth surface of spiral bevel gear by applying the differential geometry and space engagement theory, and provided an objective and quantitative method for inspecting the actual tooth surface of spiral bevel gears by using coordinate measuring machine. After comparing the coordinates of the actual gear tooth surface and the theoretical one, a high-precision analysis graphics of tooth surface errors can be obtained by measured date processing. A pair of aviation spiral bevel gears were manufactured by Phoenix 800PG grinding machine, and tested by Mahr measurement. The two results are calculated by this approach and by Mahr’s software respectively, and showing the consistency. The approach presented herein is accurate and available.

    Nonlinear Errors of Force-balanced Micro Accelerometer
    Zhou Wu,;He Xiaoping;Su Wei;Li Bailin
    2009, 20(15):  0-1770. 
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    The effects of the co-fields and structural parameters of a force-balanced accelero-meter on the sensitivity and the nonlinear errors were analyzed based on the operation principle in closed loop of systems. The conclusion reached by analytical method is that the sensitivity has nothing to do with the AC bias and gain value, and the nonlinear errors are of inverse proportional to the AC bias and gain, and cubically related to the input accelerometer. DRIE and silicon bond technologies are selected to fabricate the whole structure, and experiment on centrifuge indicates that the outcomes of test are coincident with theoretical calculation.

    Research on Pooling Inventory Optimization for Large Equipment Manufacturer’s Maintenance Parts
    Yang Hua;Guo Wei;Bi Hailing;Wu Qiaoyun
    2009, 20(15):  0-1889. 
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    Taking large equipment manufactuer’s regional maintenance part agents as the research object,a multi-location inventory optimization model was set up.This model was to minimize the total costs for inventory holding,customer waiting caused by the unavailable part and lateral transshipment subject to the total system’s level,which reprensented the fraction of demands satisfied without backordering. Numerical examples show the pooling inventory system operation costs and stocking levels are lower than that of the decentralized inventory system. With the customer waiting cost per unit of time increasing, some types of maintenance parts’ pooling inventory system’s operation costs are higher than that of the decentralized inventory system.This finding explains pooling inventory policy is fit to low -demand and high price maintenance parts.

    Description Method of Process Planning for Reconfigurable Manufacturing System
    Song Shigang;Xu Liyun;Li Aiping 
    2009, 20(15):  0-1770. 
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    A description method of process planning suitable to dynamic manufacturing circumstance was put forward after analyzing the advantages and disadvantages of various description methods of process planning. The mathematical analyses and expression mode of process planning state were presented. According to analyzing relation of state matrix, location matrix and control vector,state information of process planning was described truly using get-state-code function to receive state value on every working procedure. Based on machining state of every characteristic, process planning re-collocation was realized by reusing relevant process information, and met to full description of process planning state information in actual manufacture.

    Optimization of Cushion Characteristic of Airbag Based on Micro Multi-objective Genetic Algorithms
    Liu Xin;Han Xu;Liu Guiping
    2009, 20(15):  0-1889. 
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    A dynamics model of airbag was developed based on the thermodynamics theory.A multi-objective optimization method for the optimization of cushion
    characteristics of the airbag was suggested.The objectives were the cushion characteristic of airbag.The micro multi-objective genetic algorithm with high efficiency was adopted to search the key parameters, such as the structure of pipe,initial pressure,pop pressure and the bottom area and height of the airbag dynamic characteristics.The experimental results demonstrate that the proposed method gives an optimal design of airbag with
    reducing experimental numbers and cutting down experimental cost,and the several dynamic characteristics of airbag which can fulfill different needs are acquired efficiency.The method can also be used in the field of other airdrop protections.

    Towards a Process Cooperation Oriented Mobilized Collaborative Manufacturing Execution Platform for Complex Products
    He Yanli;He Weiping;Yang Haicheng;Zhang Wei 
    2009, 20(15):  0-1770. 
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    Mobilized collaborative manufacturing, which connects and covers the functions of manufacturing execution system (MES) inside enterprise and collaborative manufacturing system across enterprises.With the requirements to support mobilized collaborative manufacturing for complex products, this paper presented a process cooperation oriented mobilized collaborative manufacturing platform,which will help enterprises establish optimum production schedule and production reservation with due date constraints, construct virtual enterprise, and use internal and external resources to complete manufacturing activities with the coordination of multi agent system and workflow system.A prototype system was constructed and proved with a real production case study. 

    SQP Parallel Optimization Algorithm Based on Multi-domain Simulation
    Mao Huping;Wu Yizhong;Chen Liping
    2009, 20(15):  0-1889. 
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    A parallel processing and scheduling strategy of SQP algorithm in multi-domain simulation optimization was studied.We proposed the abstract scheduling model in parallel optimization problem:an discrete variable optimization model with equality constraints.Details of cluster of workstations were given,a thorough theoretical feasibility of parallel algorithm.Under the uniform modeling and simulation platform for multi-domain systems,MWorks,parallel optimization and process were implemented.The efficiency of SQP optimization of parallel technique was proved by an example of the design optimization of a simple F14 aircraft model.

    Identification of State of Continuous Rotor-blade Rubbing
    Chen Wei;Du Farong;Li Yunqing
    2009, 20(15):  0-1770. 
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    Based on the characteristics of the process that resonant wave transmitted in elastic medium, a method was developed to identify the state of continuous rotor-rubbing from the point of energy distribution. Processing signals by FFT, analyzing PSD chart and color map from energy point, and combining time domain chart and frequency chart were used to confirm the state. Through experiments, the lab results and the analysis results are identical. And this experience can be used in engineering to identify the state of rotor rubbing.

    Numerical Simulation of Three-dimensional Isothermal RTM Process Based on Solid Flow
    Shi Fei;Dong Xianghuai;Zhou Bin
    2009, 20(15):  0-1889. 
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    The modeling of control volume/finite element based on solid flow was presented for the numeral simulation of three-dimensional isothermal RTM process.The three-dimensional node control volume was renewedly programmed by using unstructured four-node body elements based on control volume/finite element theory. The control equation made up of Darcy equation and mass conversation equation was integrated in the control volume, and the model of solid flow was constructed,which explained resin flows in the fiber-reinforcemen.The computer code was developed. The results show the good calculation accuracy is obtained within several iterations when few nodes are used. Much information can be provided by using solid flow in order to explain the resin flow in the fiber- reinforcement.

    Synchronous Theory for Multi-type Self-synchronous Vibration Systems
    Zhang Nan;Hou Xiaolin;Wen Bangchun
    2009, 20(15):  0-1770. 
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    A new type of self-synchronization stability was presented, which was excited by many types of self-synchronization system.Based on predigest model for vibration synchronization driven by four motors, the equations of classical vibration were detailedly discussed, and self-synchronization and stability condition were set up in theory.Thereby, self-synchronous theory for vibration synchronization driven by four motors was inferred.From self-synchronous theory for vibration synchronization driven by four motors, self-synchronous theory for self-synchronous vibration system driven by double or more motors were inferred. The paper takes the project that syllabify and roundly sum up self-synchronous theory of multi-type self-synchronous vibration system.It is feasible to apply that synchronization stability theory to this product, and references were provided for ameliorating the design of similar products.

    Research on Dynamic Characteristics of a Novel Hybrid Journal Bearing Based on Linear Perturbation Technique
    Yang Ying;Lu Changhou
    2009, 20(15):  0-1889. 
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    The hydrodynamic lubrication of a newly developed adaptive structure journal bearing with spiral oil wedges was analyzed theoretically, and the Reynolds equation and flow balance equation were solved simultaneously by means of finite differential method in intercrossing iterative numerical calculations. Based on a linear first-order perturbation technique, the dynamic stiffness and damping coefficients were calculated, respectively. It was investigated how the dynamic coefficients were affected by the bearing parameters, finally the experimental data from a foreign paper validated the theoretical analysis. The results indicate that bearing parameters, such as spiral angle, length-to-diameter ratio and eccentricity ratio, make more influence on the dynamic coefficients, and also show that in order to obtain improved dynamic characteristics, special emphasis should be put on the design of the bearing. The comparison with the experimental data illuminates the proposed analysis and results are validated.

    Fabricating Electrode by Electrodepositing Technology and 
    Its Application in Micro-EDM Deep Hole Drilling
    Wang Jin;Wang Yuangang;Zhao Fuling;Liu Yu
    2009, 20(15):  0-1770. 
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    Electrode wear affects accuracy of micro-EDM deep hole drilling seriously.The reasons why the shape of electrode changes during micro-EDM deep hole drilling were analyzed.A method, strengthen electrical erosion resistance of lateral electrode through electroplating Cu-ZrB2 composite on copper matrix by co-electroforming,
    was put forward.Experiments of micro-EDM deep hole drilling were performed to demonstrate its correctness. Results show that the method proposed improves precision of holes.

    Electrochemical Micromachining Enhanced by Cathode Jump Motion
    Liu Zhuang;Qiu Zhongjun;Heng Chong;Qu Ningsong
    2009, 20(15):  0-1889. 
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    Cathode cyclic jump motion was implemented during the process of electrochemical micromachining herein. A linear motor was employed to carry cathode to move with high acceleration in cycles. Due to the accelerating motion of tool electrode in cycles, the electrolyte within machining gap would be partly refreshed. The Z-axis feeding motor, linear motor and DC supplier were coupled in the self-developed experimental equipment. A series of micro-holes were drilled on stainless steel (1Cr18Ni9Ti) plate with thickness of 0.5mm to investigate the presented process. Experimental results show that cathode feeding with cyclic jump, higher jump acceleration, longer jump height and shorter cyclic machining time lead to better machining accuracy.

    Study on Analytical Modeling of the Stator of Longitudinal and Torsional Hybrid Type Ultrasonicmotor
    Tao Zheng;Gao Jianshe;Zhao Chunsheng
    2009, 20(15):  0-1770. 
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    The stator of longitudinal and torsional hybrid type ultrasonicmotor (TLHUSM) was always designed as complicated configuration because of its particular principle of operation.TLHUSM’s analytical model was educed detailedly herein based on Lagrange equation, electromechanical coupled equation and mode superposition principle. The mathematics model can be applied to calculate varying modal parameters of the stator easily. Finally the computational results of the model were compared against those from the finite element method and experiments. Thus a high computational efficiency of the model are demonstrated and it proves that the proposed model can be used in the performance simulation and optimization design of the motor systems.

    Dynamic Testing Technology for Microstructure in High-g Acceleration
    Wang Tao;Wang Xiaodong;Wang Liding
    2009, 20(15):  0-1889. 
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    To study the dynamic characteristics of microstructures in high g acceleration environment, the dynamic testing technology in high g acceleration was systematically studied and the dynamic testing equipment was developed. The high g acceleration environment was generated by the centrifugal acceleration produced with the high speed centrifugal turntable. The base excitation device which used the piezoceramics as the driving source was established and the impulse excitation in high g acceleration was implemented. With built-in self-testing(BIST) technology, the dynamic response signals of the microstructure were obtained by the integrated sensing element in it. Using the dynamic testing equipment, the experiments for microstructures in different steady high g accelerations from 0g to 10 000g were performed, and the dynamic characteristics of the microstructure such as natural frequency and damping ratio were obtained. The experimental results show when the microstructure is in large deflection under external high g-force, the natural frequency of the microstructure gets higher as the acceleration increases.

    Research on Characteristics of Oil Film for Work Interface in Metal Rolling Processes
    Wang Qiaoyi;Li Zhihua
    2009, 20(15):  0-1770. 
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    On the basis of rolling theory and hydromechanics theory,a basic film thickness model of work interface in metal rolling processes was developed. The inlet film thickness was defined by the analysis of the inlet zone, and the influence of unsteady variables such as inlet angle, strip tension stress and rolling speed variation on inlet film thickness were investigated, and the analysis of linear solutions and frequency response of inlet film thickness was made. The analysis of the unsteady work zone was based on the known inlet zone.rolling mill in a certain corporation was chosen as the subject for the study. Using simulation program, the influence of some main parameters on the film thickness distribution of work zone and inlet zone was analyzed quantitatively.The calculatrd results indicate that avoiding low frequency back tension stress and roll speed variations which may cause inlet film thickness variations.Secondly,high frequency rolling mill vibrations should definitely be avoided since they may induce a high frequency inlet angle change which will in turn dramatically increase the inlet film thichness variation.

    Influence of Die-rivet Volume Ratio on Forming Performance 
    of Self-piercing Riveting Joints of Dissimilar Materials
    Lou Ming;Li Yongbing;Huang Shuyan;Chen Guanlong
    2009, 20(15):  0-1889. 
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    This paper developed the influence of die-rivet volume ratio on self-piercing riveting joints of Al-to-steel and steel-to-Al combinations separately. The experimental results show that both joints of Al-to-steel and steel-to-Al combinations has larger undercut quantity when die-rivet volume ratio is larger than 1; meanwhile, for joint of steel-to-Al combination, larger die-rivet volume ratio is propitious to minimize the gap between the inner surface of rivet and upper surface of top steel sheet and that will insure the tightness of the joint.

    Analysis of Thermal Influence of Si Processed with Femtosecond Laser 
    Miao Enming
    2009, 20(15):  0-1770. 
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    The interaction of the radiation of Ti:sapphire femtosecond laser (wavelength 800nm,130fs) on silicon wafers in air was measured using a scanning electron microscopy and thermal influence rule in the surface of material with femtosecond laser miacromachining. Thermal influence can not be ignored in practice by processing hole on the surface of Si. The thermal influence rule of the morphology of the holes is obtained with 10 pulse numbers. The optimal femtosecond laser fluence extension in processing holes is confirmed.

    New Technology of Twin Symmetry Roll Axial Rolling Passive Spiral Bevel Gears 
    Zhu Chundong;Shi Shuangxi;Hua Lin
    2009, 20(15):  0-1889. 
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    The principle of twin symmetry roll axle-mill was introduced.A new process was proposed which was for twin symmetry roll axial rolling passive spiral bevel gears.The deformation process by the new technology was analyzed by rigid plastic FEM software.Rolling force was calculated in theory.According to the simulation and calculation result,the processing experiments of rolling spiral bevel gear were finished in twin symmetry roll axle-mill.The results show that new technology can achieve full of the spiral tooth form and the forming force is small.The passive spiral bevel gear of 246 is warmly formed,whose force is about 2000kN.

    Research on Regenerative Braking Control Strategy for 
    Parallel Hydraulic Hybrid Vehicles Based on Backward Modeling
    Liu Tao,;Jiang Jihai;Sun Hui
    2009, 20(15):  0-1770. 
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    Based on the analysis of the braking characteristics in the city drive cycle and high power density of hydrostatic drive hybrid vehicles, considering the effects of vehicle load weight and propulsion mode on regenerative braking performance, a regenerative braking control strategy for parallel hydraulic hybrid vehicles (PHHV) was proposed.A backward simulation model of PHHV was built with numerical modeling and theoretical modeling methods. Hydraulic regenerative braking was researched under typical driving cycles using the backward simulation model for PHHV and the results show that the control strategy and the models are accurate and applicable, and the braking energy under the premise of safety brake can be regenerated effectively.

    Application of Thin-walled Beam Lightweight Based on Reliability of 
    Mulitidisciplinary Design Optimization
    Zhang Yong;Li Guangyao;Zhong Zhihua
    2009, 20(15):  0-1889. 
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    The thin-wall beam that has a major impact on the safety of the body was optimized, the design of the thin-walled beam was proposed,which was necessary to consider safety, static load-bearing characteristics and the first order vibration mode. At the same time, the process of optimizing design involved material, size, layout of the spotwelds, and many other parameters, the traditional deterministic optimal design results often converged to the subjecting border, and could not meet the reliability requirements of product design.Combined with design of experiment, response surface models, reliability theory and genetic algorithms, the reliability of multidisciplinary design optimization method of thin-walled beam was constructed based on the product quality engineering.Comparing with the traditional deterministic optimization results, we know that reliability optimization results meet better the established lightweight objectives, and make thin-walled beam reliability a notable increase.