Loading...

Table of Content

    25 May 2010, Volume 21 Issue 10
    Reliability Sensitivity Design for a Turbine Disc with Low Cycle Fatigue Failure
    ZHANG Xi-Min, WANG Feng, YANG Zhou, ZHANG Fei
    2010, 21(10):  1135-1139. 
    Asbtract ( )   PDF (3560KB) ( )  
    References | Related Articles | Metrics
    Based on the finite element method,a low cycle fatigue model,
    RBF neural network technique and reliability theory, the reliability sensitivity design for one turbine disc with low cycle fatigue failure were studied in detail.First, the explicit relational expression among the design parameters and the failure life were given in term of RBF neural network. On the basis of the trained neural network,the MPPPM can be used to begin the sensitivity design. Hence,the introduction to RBF neural network solves the explicit expression of the limit state function which is difficult to obtain in engineering, and the method of sensitivity which expresses the influence the parameters posed on the reliability in quantity has a strong significance.
    Research on Elastic Sleeve of Piezoelectric Ceramic Driver
    CHENG Ling-Li, TU Xiao-Fen, TU Qing, HU Jia-Wen
    2010, 21(10):  1139-1142. 
    Asbtract ( )   PDF (2943KB) ( )  
    References | Related Articles | Metrics
    The decision-making of  a novel elastic sleeve was developed,which can protect unsealed piezoelectric(PZT) ceramic driver,for the problem of unsealed PZT extremely easy to be damaged,cannot withstand the shearing force and the very expensive price.According to elasticity theory principle,a circular cylinder sleeve was partially cutted to form elastic elements to generate elastic deformation.By modificating the dimensions of an elastic sleeve,it can optimize displacement and stresses.The driving force model of elastic sleeve was established.The displacement characteristic experiments of PZT setted in elastic sleeve were performed.The experiments show
    elastic sleeve does not affect PZT's performance and can protect PZT,moreover it is
    processed easily,so it may be widely used.
    Real-time Solution of Inverse Kinematics Problem of Multi-joint Robots
    YI Feng, WANG Yao-Na, JIA Han-Min
    2010, 21(10):  1143-1148. 
    Asbtract ( )   PDF (4081KB) ( )  
    References | Related Articles | Metrics
    Due to the highly nonlinear and complex nature of the manipulator kinematic equations, the solution of the inverse problem is difficult to achieve and it
    is difficult to guarantee in real-time.A new method for computing solutions to the inverse kinematics of robotic manipulators was developed herein.The proposed method was
    based on an EM algorithm,by randomly sampling points from the feasible region, similar to attraction-repulsion mechanism of the electromagnetism theory,the particles rapidly converge to optimal solution.Moreover,approximate optimal solution derived by EM was used for the initial guesses value of variable metric method to search the exact solution. Nevertheless, the exact optimal step size in search is usually difficult to achieve.For this problem, approximate formulas for calculating were derived based on motion differential equation of robot when step size was sufficiently small.Finally,some examples were taken to verify the effectiveness of the algorithm.
    Simulation and Analysis of Magnetic Particle Clutch
    ZHOU Yun-Bei, CHANG Sai-Qi
    2010, 21(10):  1149-1152. 
    Asbtract ( )   PDF (2832KB) ( )  
    References | Related Articles | Metrics
    This paper presented a method of magnetic particle clutch simulation and analysis by using three-dimensional magnetic field simulation analysis.Through Ansoft software,a three-dimensional model of magnetic particle clutch was built.The relationship between torque and exciting current, property of torque and slip were analysed by a more accurate self-adaptive grid. The results show that simulation data corresponds to test data. Quantitative relationship between main design parameters of magnetic particle clutch and performance was identified.It can be used as the basis for magnetic particle clutch optimum
    design.
    New Design of Positive Amplitude Time-delay Filter with Tail Signals 
    WANG Xiao-Jun
    2010, 21(10):  1153-1156,1178. 
    Asbtract ( )   PDF (3335KB) ( )  
    References | Related Articles | Metrics
    For flexible systems with zeros,a new positive time-delay filter with tail signals was designed,which can suit for any shaped system inputs.And the design procedure is not dependent on the system output reference.And the robustness constraints were proposed to increase the insensitivity to the system parameter variations.Applications in the positioning and anti-sway of overhead cranes verified the fine performance of this strategy.The proposed approach can reduce the regulation time of the trolley positioning.And the approach cascading with normal time-delay filter can eliminate load residual vibration,which can improve the operational efficiency.
    Helicopter Rotor Vibration Reduction Optimization by Modal Shaping of Blades
    WANG Gong-Zhou, LIU Yong, ZHANG Cheng-Lin-
    2010, 21(10):  1157-1161. 
    Asbtract ( )   PDF (3823KB) ( )  
    References | Related Articles | Metrics
    Wang Hongzhou;Liu Yong;Zhang Chenglin
    National Key Laboratory of Rotorcraft Aeromechanics, Nanjing University of Aeronautics and Astronautics, Nanjing,210016
     The aeroelastic and modal shaping finite element dynamics model was derived from Hamilton theory. It can be analyzed the systematic structural dynamics by changing the stiffness and mass of blade section. The stiffness and mass of blade section were used as design variables, constraints on frequency placement, autorotational inertia, mass and MSP were included, the objective function was to minimize the blade vibration. Finally, compared with the optimization results of the designed model, the result shows that the optimum solution results will cause 55.4% reduction of the 3/rev rotor blade root shears, 66.5% reduction of 4/rev rotor blade shears and 53.4% reduction of the 5/rev rotor blade shear under the constrained conditions.
    Research on Energy Regeneration System of Hydraulic Excavator's Boom Based on Hydraulic Transformer
    ZHANG Shu-Zhong, DENG Bin, KE Jian
    2010, 21(10):  1161-1166. 
    Asbtract ( )   PDF (4151KB) ( )  
    References | Related Articles | Metrics
    In order to improve the efficiency of hydraulic excavator's boom,an energy saving system for hydraulic boom was brought forward,which can accomplish potential energy recovery and reutilization by hydraulic transformer,adopting an accumulator as energy storing device. Firstly, the composition and working principles of the system were discussed.Then models of working set and hydraulic system were established.Simulation under typical working cycle presents,the amount of boom potential energy,recovered energy,reutilized energy and regenerated flow volume.Furthermore,the energy consumption of boom was analyzed and compared with the original hydraulic system.After analysis,it shows that the system runs steadily and comfortably,saves energy remarkably by potential energy reutilization and flow regeneration,has good potential for improving energy utilization of hydraulic excavator.
    Multi-objective Flexible Job-shop Scheduling Based on Strength Pareto Evolutionary Algorithm
    WANG Yun, TAN Jian-Rong, FENG Yi-Xiong, LI Zhong-Kai
    2010, 21(10):  1167-1172. 
    Asbtract ( )   PDF (3985KB) ( )  
    References | Related Articles | Metrics

    To solve FJSP, a multi-objective FJSP optimization model was set up, concerned with time, cost and delivery satisfaction. The optimal solutions were obtained by using improved SPEA. The SPEA was improved by introducing the fuzzy C-means clustering algorithm to accelerate the clustering procedure within the external population. With the constraint Pareto domination concept and the two-level representation schema, a Pareto optimal set could be achieved in a single run. Then the preference sequence of Pareto solutions was achieved and a solution was extracted as the best compromise one based on set theory. The feasibility and validity of the proposed algorithm have been proved by the results in a workshop scheduling.  flexible job-shop

    Study on Job Shop Scheduling Problems Based on Microhabitat Ant Colony Optimization
    GAN Ge, LI Qing, ZHANG Zhi-Wei
    2010, 21(10):  1173-1178. 
    Asbtract ( )   PDF (3981KB) ( )  
    References | Related Articles | Metrics
    Simulating the parallel and multiform optimized actions of ant colony, basic scheduling rules of ants (BSRA) were built up. To improve the optimized performance, microhabitat ant colony optimization stratage (MACOS) was built up to improve basic ant colony optimization (ACO) by pheromone time-varying distribution, pheromone updating tactic and information exchanging mutation. Ant colony optimization scheduling rules (MACO SR) were built up based on MACOS to solve JSSP. And waiting time was integrated into the heuristic function and path updating of MACO SR. MACO SR can achieve more satisfactory results than basic ACO and BSRA for JSSP with the objects function of minimum make-span. And MACO SR also shows significant optimization performance.
    Research on Reconfigurable Plant Layout Based on Equipment Capability
    SONG Shi-Gang, LI Ai-Beng, XU Li-Yun
    2010, 21(10):  1179-1183. 
    Asbtract ( )   PDF (3535KB) ( )  
    References | Related Articles | Metrics
    To improve enterprise's market-response ability and competitiveness,the reconfigurable plant layout flow of a reconfigurable manufacturing system was proposed.According to machining process of products,equipment layout was optimized gradually based on current layout and equipment machining state.Mathematic model was presented with considering materiel transport cost,equipment reset cost and production loss cost. Its objective was to minimize cost of reconfigurable plant,and realize reconfigurable plant layout based on equipment capability using dynamic programming algorithm.An application example validates the efficiency and feasibility of the above method.
    Process Model of Production Quality Management System Based on Resource-logic Dynamic Coupling
    DUAN Gui-Jiang, XU Qiang-Feng
    2010, 21(10):  1184-1189. 
    Asbtract ( )   PDF (4422KB) ( )  
    References | Related Articles | Metrics
    To improve the ability of process control and flexibility in modern quality management system,a process model of production quality management was analyzed and a process management model based on configuration was put forward. In this model, the process of production quality system was separated into routing logic and process resources. The routing logic described the action was accurately executed according to the given conditions and orders.The process resources described the resources which the process needed such as the workers, data, restriction and so on. The flexible production quality management process was realized through the dynamic coupling of logic and resources. Finally, the development and application of the production quality management system based on the configurable process management model was introduced in detail.
    Time Synchronization of Wireless Sensor Networks for Mechanical Vibration Monitoring 
    SHANG Bao-Beng, CAO Xiao-Jia, ZHANG Guo-Lei
    2010, 21(10):  1190-1194. 
    Asbtract ( )   PDF (3647KB) ( )  
    References | Related Articles | Metrics
    By analyzing the effects of the multi-node time synchronization errors on mechanical vibration monitoring,it is indicated that the characteristics of time synchronization on mechanical vibration monitoring must be microsecond-level accuracy,low overhead and multi-hop synchronization.A low overhead multi-hop time synchronization approach was proposed herein.a known single hop synchronization approach was extended to multi-hop synchronization by employing a greedy heuristic algorithm to select reference nodes.The simulation and experimental results reveal that the proposed approach has the same synchronization accuracy as the well-known schemes reference broadcast synchronization and significantly reduces the energy consumption, which show that the proposed approach has a better performance for the mechanical vibration monitoring application.
    Multi-disciplinary Collaborative Simulation of Aircraft Ground Maneuvers Based on Virtual Prototype Technology
    ZHANG Meng, NIE Hong, SHU Ru-Feng, XIONG Dun-Jie
    2010, 21(10):  1194-1199. 
    Asbtract ( )   PDF (4240KB) ( )  
    References | Related Articles | Metrics
    A new method called multi-disciplinary collaborative simulation was presented for research of aircraft ground maneuver characteristics.The virtual prototype established in ADAMS/Aircraft which was taken as core and was validated by the results of drop and static loads tests, integrated with the aircraft and landing gear geometry components built in CATIA.The flex parts exported from PATRAN/NASTRAN, and the control system established in MATLAB,were used to implement the multi-disciplinary collaborative simulation of aircraft ground maneuvers, such as, ground steering, anti-skid braking,and shimmy.The results show that: this method can model aircraft ground maneuvers accurately,and some useful conclusions are obtained. 
    Study on Optimization Model of Rolling Parameters of High Speed Rail by Universal Mill
    GUO Yu-Jing, XIE Zhi-Jiang, WANG Pan-Zhong, DAO Gong-Meng, YANG Ai-Fan
    2010, 21(10):  1200-1202,1207. 
    Asbtract ( )   PDF (2841KB) ( )  
    References | Related Articles | Metrics
    According to the characteristics of strong coupling of variables for universal rolling line of high speed rail,taking the rolling precision of rail section as the goal, it established an optimization model of rolling parameter of rail by combining the optimization-range algorithms with neural network.Corresponding relation among rolling course data and rail section gather data was set up, the dominant interzone was utilized to obtain initial value of roll gap and rolling strength under the particular working condition after preconditioning of the data, and the neural network was used to revise initial value. It has proved that this model can reduce the influence of the subjective factors and improve the rolling precision of the rail. 
    Research on Pressure Pulsation Characteristics of Axial Piston Pump Based on Virtual Prototype
    XU Bing, LI Chun-Guang, ZHANG Bin, HU Shu-Sheng
    2010, 21(10):  1203-1207. 
    Asbtract ( )   PDF (3509KB) ( )  
    References | Related Articles | Metrics
    Virtual prototype technology(VPT) applied in axial piston pump simulation research was introduced. Dynamics model and hydraulic model of piston pump individually grounded on MSC.ADAMS and AMESim were built by means of VPT and actual piston pump parameters. Solid-liquid coupling virtual prototype of axial piston pump was put up based on the interface of the two models. Pressure pulsation of piston pump affected by oil viscosity and bulk modulus was investigated based on the virtual prototype. Pressure pulsation amplitude and rate increasing with bulk modulus as linear relationship while with viscosity as descending relationship are concluded.
    Study on Design of a 4R1P-active Balancer 
    ZHANG Yang, TAO Yan-An, CHA Jian-Zhong
    2010, 21(10):  1208-1213. 
    Asbtract ( )   PDF (4146KB) ( )  
    References | Related Articles | Metrics
    A 4R1P-active balancer was an independent device,consisting of a planar two-DOF 4R1P mechanism and a controllable motor.One input shaft of the 4R1P mechanism doubled as its output shaft,connected to the machine to be balanced.The another input was driven by a control motor.One or more dynamic effects of the mechanism can be minimized by selecting speed trajectories and structural parameters of the 4R1P mechanism properly.An optimization model was developed based on the input torque,
    the shaking moment, the shaking force and the maximum power of the control motor.
    And the design procedure was put forward.Taking a force-balanced crank-rocker mechanism as the reference mechanism, numerical examples were given to demonstrate the effectiveness of the proposed balancer. The results show that flexible dynamic balancing effect on the dynamic performance under different working conditions can be achieved by attaching the proposed balancer to both of the output shaft and the input shaft of the machine to be balanced. The deterioration of dynamic factors caused by alterative working conditions can be compensated effectively by redesigning the control parameters of the balancer.
    Improvement of Impact Wear Performance of Ti6Al4V Alloy by Nitrogen Ion Implantation and Nitriding  
    WANG Yan, ZHONG Rong
    2010, 21(10):  1214-1217. 
    Asbtract ( )   PDF (2913KB) ( )  
    References | Related Articles | Metrics
    Ti6Al4V alloy was modified by high frequency and low voltage plasma immersion and ion implantation(HLPIII).The impact wear tests were carried out with a new small load impact-wear testing machine.Contrast test was done with untreated sample by HLPIII. Results show that the treated sample by HLPIII has lower impact-depth under the same impact-force and impact-number,and has higher critical impact-number under the variable impact-force.HLPIII treating can effectively reduce adhesivity and increase impact-wear performance of Ti6Al4V alloy. 
    FEM Analysis of Contact Problem of Sliding Block under Dry Friction Based on Stribeck Friction Model
    TANG Jin-Yuan, ZHOU Wei, CHEN Sai-Yu
    2010, 21(10):  1218-1221,1259. 
    Asbtract ( )   PDF (3583KB) ( )  
    References | Related Articles | Metrics
    Based on finite element theory, the contact problem of sliding block was studied with the application of Stribeck friction model, and the stress and displacement distribution of sliding block were obtained. The numerical results show that: the stress distribution on contact surface is relative to the relative velocity of sliding block and friction coefficient, and the maximum relative error of stress can be 100.08%. The non-linear Stribeck friction model can better describe the real situation of contact surface, because of the consideration of impact of the relative velocity to the friction. Finally, with the designed program and ANSYS software, the comparison of the stress distribution under Coulomb friction condition was presented, which validated the accuracy of the designed program. 
    Rapid Simulation of Sheet Forming Based on GPU
    WANG Jian-Hua, LI Guang-Yao, LI Qing, SUN Guang-Yong, WU An
    2010, 21(10):  1222-1227. 
    Asbtract ( )   PDF (4467KB) ( )  
    References | Related Articles | Metrics
    In order to eliminate the lasting calculation bottleneck on application of finite element,we proposed a new method to accelerate the computation of FEM by using the existing modern GPU and programmable shading tool. In accordance with the features of GPU,we devised a method representing unit information and initial conditions,which converted all the unit calculations into rendering process.In this way,the simulation work of all the unit calculation of the internal force will be solved,and the shortcomings of lowly parallel level appeared ever before when it run in a single computer can be overcome.Studies show that this mean can improve efficiency and shorten calculating hours greatly.Aimed at the elasticity problem of large number cells in a sheet metal,the GPU parallel simulation calculation rate will be faster than
    that by using the CPU's,as well as it has useful and practical value in solving the project problems.
    Finite Element Analysis of Plate Laminated Composite Structures Based on Deformation Compatibility
    CHEN Li-Hua, HUANG Meng-Hui, BANG Wei-Bei
    2010, 21(10):  1227-1231. 
    Asbtract ( )   PDF (3710KB) ( )  
    References | Related Articles | Metrics
    Plate laminated composite structure is a key part of the heavy-duty forming equipment,which can transfer and diffuse the concentrated load evenly into body structure of the heavy-duty forming equipment to modify the state of stress of the whole equipment.However,the plate laminated composite structures designed by conventional structural strength method,often causes local concentration of load due to the deformation disagreement among the laminated plates and can not really realize evenly diffused transmission of the concentrated load.A three-dimensional finite element model of plate laminated composite structure,preloaded by bolts was built based on the Marc software platform.Via changing the whole height of such composite structure, different combinations of plate thicknesses and adjusting the distribution of preloaded bolts,the transmission rule of the force flow among laminated plates and their contact interfaces were studied.The concentrated load transfer uniformly among the laminated plates is realized.
    System Design of a Needle-free Injector for Animal Vaccination
    CHEN Kai, ZHOU Hua
    2010, 21(10):  1231-1234. 
    Asbtract ( )   PDF (2952KB) ( )  
    References | Related Articles | Metrics
    A spring-powered jet injector was designed for animal vaccine injection.It has the feature of continuous drug delivery and injection.Several parameters are critical to the injection quality,such as nozzle diameter,volume of drug delivered,ampoule diameter,and jetting force.As two important factors to evaluate the injection quality,the injection pressure determines whether the jet can erode and penetrate
    into the skin,and the jet power effectively describes the injection completeness.A physical model was presented to predict the injection pressure and jet power with given system parameters.The model was validated by experimental results.Finally,an example was given to determine the system variables through calculation.
    Study on Continuous Casting Billet Surface Defect Detection Based on Pulsed Eddy Current Technique
    OU Yang-Ai, ZHANG Min, DIAO Li-Meng, ZHANG Li-Zhi
    2010, 21(10):  1235-1239. 
    Asbtract ( )   PDF (3423KB) ( )  
    References | Related Articles | Metrics
    In order to realize surface and near-surface defect on-line monitoring and sorting for high temperature continuous casting billet,a PEC methods was proposed and experimental studies were carried out.Through differential signal analysis and time-domain analysis for the detection coil output signals of eddy current sensor,the feature parameters,such as voltage peak,peak time and zero-crossing time,were extracted,and the impact law of the parameters was studied for point defects,lines defects and star cracks.The research shows that the PEC technology for surface defect monitoring of high temperature continuous casting billet is feasible,and the feature parameters,such as voltage peak,peak time and zero-crossing time,are related closely to defect kind and form,and is laid the foundation for further study on surface defect detection on-line for high temperature continuous casting billet.
    Research on Machining Notches of Connecting Rod by WEDM
    LIU Xiao-Ning, TANG Yong-Jun, ZHANG Yong-Dun
    2010, 21(10):  1240-1245. 
    Asbtract ( )   PDF (4326KB) ( )  
    References | Related Articles | Metrics
    In order to resolve the problem of connecting rod notches machining, a new process of WEDM was presented,processing parameters of notch were analyzed, and project of machining notch using WEDM was introduced,including measures to achieve good quality notch.The relationship among cutting speed and power supply parameters was investigated,and it is discovered that micro-cracks in bottom of notch are greatly effect on fracture splitting process,a new idea of active controlling micro-crack was also presented.Finally,reasons of fracture splitting only one side and wire electrode cracking were analyzed,and fracture splitting machining was carried out.
    Mechanism of Chemo-mechanical Polishing Process for Silicon Nitride Balls
    SHU Cong-Rong, LV Bing-Hai, YUAN Ju-Long
    2010, 21(10):  1245-1249. 
    Asbtract ( )   PDF (3527KB) ( )  
    References | Related Articles | Metrics
    To investigate the chemo-mechanical polishing process and the interaction between abrasive and workmaterial,experiments were carried out with four different abrasives.The roughness of the polished ball surface with different abrasive was discussed.The removal mode of workmaterial was also analyzed with obtained SEM images of Si3N4 ball surfaces.XRD was used to test the production of the chemo-reaction between abrasive and workmaterial.The test results are consistent with the theoretical thermodynamic analysis.The results herein show that the CeO2 is an effective abrasive to polishing Si3N4 balls,and an smooth surface with Ra 4nm is obtained in chemo-mechanical polishing.
    Present State and Perspectives of Estimation Research for Several Key States and Parameters in Vehicle Dynamics
    DIAO You-Qun
    2010, 21(10):  1250-1253. 
    Asbtract ( )   PDF (2647KB) ( )  
    References | Related Articles | Metrics
    The significance to develop estimation research for several key states and parameters in vehicle dynamics was discussed,and the research methods were summarized.The connotative meanings were described for the estimation of several key states and parameters in vehicle dynamics,and the main research methods and some application examples were given.Finally,the most important problems were presented,and the research can present some basic theory of vehicle dynamics modeling and vehicle
    chassis control.
    Research and Development of Small In-pipe Robots
    JIAO Jin-Wai, CHANG Jian-Zhong, CHEN,XUN,LUO Zi-Rong
    2010, 21(10):  1254-1259. 
    Asbtract ( )   PDF (3871KB) ( )  
    References | Related Articles | Metrics
    Based on special application occasions,the small in-pipe robots working in the non-liquid pipes were divided into three types,wheel type,inchworm type and quiver type.Then,each type was classified again by different drivers,whose development process,present status,advantages,shortages and application situation were described particularly.After this,the research of small in-pipe robotics was separated into four stages,which indicated the design and optimization of locomotive mechanism,the design of special sensors,realization of wireless energy and signal transmission and self control.It has successfully made the research work of small in-pipe robots clear.