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ISSN 1674-2850
CN 11-9150/N5
 
Current Issue
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February 30,2012
Volume 5,Issue 4
Pages -
Subject Area:Electromechanics,Electric Materials,Electric measurement Technology and Instrument,Electric Power System and Automation,Cutting Processing Technology
 
Title: A kind of ultrasonic motor drive circuit based on series resonance
Authors: PAN Peng, HU Minqiang, XU Zhike
PP: 383-386
Abstract: This paper analyzed the driving mechanism of the ultrasonic motor (USM), obtained that even the AC voltage which has DC bias can also drive the USM. Based on inductance and capacitance (LC) series resonance and the USM equivalent circuit, a kind of drive circuit scheme was designed. The parameters of the circuit depend on the LC amplitude-frequency characteristics. In the end, this paper showed the experiment result in figures, which proved the feasibility of this drive circuit scheme. At the same time, this scheme eliminated the use of transformer, effectively reduced the size of circuit.
Keywords: electromechanics; ultrasonic motor; drive circuit; series resonance
 
Title: Identification of J-A magnetic hysteresis mathematical model parameters using simulated annealing method
Authors: BAI Baodong, WANG Jiayin, ZHANG Jian, YANG Guohui
PP: 377-382
Abstract: This paper presents a method and the experimental measurement system for the identification of J-A (Jiles-Atherton) magnetic hysteresis mathematical model parameters of the 30ZH120 silicon steel sheet. The paper utilizes Epstein Square devices to process the experiment and measurement on a group of hysteresis loops of some certain transformers which use the 30ZH120 silicon steel sheet under two different lap ways. The approach relies on simulated annealing optimization method in order to minimize the error between the measured and modeled hysteresis curves and yield the best five J-A model parameters. A convenient program based on the Simulink platform is developed that can identify the J-A model parameters automatically from experimental saturated hysteresis loop which is used to model the nonlinear characteristics of the silicon steel sheet. Research shows that simulated annealing optimization method gets satisfactory results.
Keywords: electric machines and electric apparatus; silicon steel sheet; parameter identification; simulated annealing method; Jiles-Atherton model
 
Title: Research on intelligent fuzzy boundary modular neural networks in gas prediction
Authors: FU Hua, YANG Yikui, LI Xinxin
PP: 372-376
Abstract: The paper proposes a neural network algorithm based on intelligent fuzzy boundary modular and applies it to gas forecast. According to the ‘divide and rule’ thought, the paper uses the genetic algorithm which adopts automatic optimization mechanism to divide the input of the automatic modular, and sets a fuzzy boundary zone based on certain fuzzy membership according to user-defined fuzzy membership functions on one side of the division boundary, which can solve the leap problem of predictive control results near module partition. Finally, the module divided samples with corresponding neural network are respectively trained, and the prediction results are concluded through the forecast synthesis module. Compared with the single neural network model, this method has improved the learning efficiency, generalization ability and accuracy of prediction model effectively. The experimental results show that the algorithm has advantages and effectiveness on gas forecast model.
Keywords: electric measurement technology and instrument; modular neural networks; genetic algorithm; gas forecasting; fuzzy boundaries
 
Title: Composite load model of tractive power supply system based on PSASP
Authors: LI Xinran, JIANG Zidan, LI Jinxin, ZHANG Yongwang, WANG Yanan, LIU Qianyong, PAN Yuan
PP: 367-371
Abstract: In order to improve simulation accuracy using user-defined model, the interface of special load model with power system analysis software package (PSASP) is studied. A load model of traction power supply system is used in simulation by PSASP/user-defined program interface (UPI). The method and step of interface realization are discussed in the paper. The model dynamic characteristics in EPRI-36 bus test system are presented and analyzed by power system transient stability simulation, and dynamic response of the model is obtained. The correctness of interface is also analyzed and discussed.
Keywords: electric power system and its automation; power system analysis software package/user-defined program interface; traction load model; transient stability; simulation
 
Title: Modeling, simulation and analysis of a controllable mechanical metal forming press
Authors: TIAN Yongli, LUO Zhenjun, ZHANG Ziqian
PP: 360-366
Abstract: A modeling language for multi-domain physical systems called Modelica was employed to establish simulation models for the controllable mechanical metal forming press. The models include a constant speed motor, a servo motor, a multi-body mechanism, a controller, etc. Further a trajectory planning function module and an inverse kinematics function module were also programmed. The input current and output torque of the two motors were simulated. The multi-domain simulation models combine the domains of mechanics, electrics, and control in a unified form and hence can perform simulation in a unified platform. Simulation results show that the punching resistance to the motors has an impact on control currents and output torques of the motors. The research provides the basis for optimizing control system and thus improves the dynamic characteristics of the press.
Keywords: mechanism; hybrid drive; modeling; simulation analysis; Modelica
 
Title: Study on boundary extraction of double side welds of pipe based on real-time X-ray imaging
Authors: SHI Han, SHAO Jiaxin, DU Dong, WANG Li
PP: 354-359
Abstract: Considering the characteristics of double edges, high noise and low contrast ratio in real-time X-ray images, the outer and inner weld boundary extraction algorithm is studied. Based on the grey-level profile analysis column by column, two algorithms, including grayscale linear transformation with double adaptive thresholds and inner edge automatic growing algorithm, are developed to extract inner and outer weld edges. Experiments show that the proposed method is efficient and reliable.
Keywords: materials processing engineering; real-time X-ray detection; welding by both sides; weld segment; image processing
 
Title: Research on real object binocular reconstruction and rendering method of geometric consistency
Authors: SUN Hao, SONG Jingzhou, JIA Qingxuan, SUN Hanxu, GAO Xin
PP: 347-353
Abstract: To solve the interaction issue of real and virtual scene, this paper provides a method based on OSG and ARToolkit, which make the “avatar” be geometrically consistent (position and orientation etc.) with the real object in keyframe in order to realize the registration of “avatar”. The “avatar” is got by binocular reconstruction. This approach needs no prior knowledge, thus it is fit for unknown or shape-changing surroundings and is rapid enough for real-time application.
Keywords: mechanical manufacture and automation; augmented reality; binocular reconstruction; geometric consistency
 
Title: Experimental study on high speed milling of TC4 titanium alloy with variable pitch milling tools
Authors: ZHAO Wei, HE Ning, LI Liang, LI Haibin
PP: 342-346
Abstract: High speed milling experiments for TC4 (Ti6Al4V) titanium alloy using regular and variable pitch milling tools are undertaken to investigate the characteristics of cutting forces, sound pressures, acceleration signals under different cutting speeds. Meanwhile, comparisons are made to discuss the influence of regular and variable pitch milling tools on the surface finish based on experiments on maximum depth of cut. The results showed that, the effective pitch distribution can inhibit the cutting vibration, increase the maximum depth of cut, and increase cutting efficiency under the appropriate cutting parameters.
Keywords: mechanical manufacturing technology and equipment; high speed milling; variable pitch milling tools; titanium alloy; maximum depth of cut
 
Title: Research on slewing bearing load distribution of a single row four point contact ball
Authors: HUANG Haoran, RUI Xiaoming, WANG Yang
PP: 336-341
Abstract: Based on the Hertz elastic contact theory, static equilibrium equations on four point contact ball bearing are established which are figured out numerically by Newton-Raphson. A typical model of slewing bearing is used as a case for calculating the load distribution. The influence laws of the rolling element center circle diameter and the rolling element diameter on load distribution of single row four point contact ball slewing bearings are researched. The results show that increasing the rolling element center circle diameter and reducing the rolling element that all lead to increase the rolling element number can improve bearing carrying capacity, and the former has more pronounced effect.
Keywords: mechanical design; slewing bearing; load distribution; rolling element diameter; rolling element center circle diameter
 
Title: Analysis on dynamic characteristics of large vibrating screen
Authors: ZHANG Jie, SONG Guangying, LI Ying, LI He, WEN Bangchun
PP: 331-335
Abstract: Modal analysis and harmonic response analysis are proceeded in software HyperMesh and OptiStruck, getting the natural frequency, the main modal type of a big scale cold sinter vibrating screen and typical frequency response curve, which provide reference for designing and choosing parameters, in order to ensure the vibrating screen operate efficiently. The results show that the natural frequency is far greater than the frequency of the screen, so there will not be resonance during working and the design of the screen is proper.
Keywords: machine design; vibrating screen; modal analysis; harmonic response analysis
 
Title: Study on roughness of high volume SiCp/Al MMCs with ultrasonic high-speed milling
Authors: XIANG Daohui, YUE Guangxi, LIU Haitao, ZHAO Bo
PP: 326-330
Abstract: The orthogonal analysis and single factor analysis are used to analyze the roughness of SiCp/Al MMCs with ultrasonic high-speed milling and high-speed milling. The influence degree and law of milling speed, feed and milling depth on the roughness are studied. The research indicates that the roughness of ultrasonic high-speed milling is lower than high-speed milling at the same condition. At the same time the optimal parameters of ultrasonic high-speed milling is obtained, which has guiding significance for finish machining of SiCp/Al MMCs.
Keywords: machine design manufacturing and automation; ultrasonic high-speed milling; polycrystalline diamond tool; surface roughness; SiCp/Al MMCs
 
Title: Information processing method of mark points for free-form surface vision measurement
Authors: SUN Junhua, GENG Yun
PP: 321-325
Abstract: In this paper, information process of mark points was proposed for free-form surface measurement, in order to satisfy the need of 3D measurement using mark points. The mark points contain coded mark points and uncoded mark points. The proposed method calculated the centre of the mark points using some geometry characters. A geometry character based decode method was proposed, using the area and angle information of the connected areas. It is proved that the proposed method is convenient and easy to realize, also with high accuracy.
Keywords: measurement technology and instrument; mark points; vision measurement; image processing; free-form surface
 
Title: Research on active sound absorption of magnetorheological fluid based on fuzzy control theory
Authors: DING Lvhui, HUANG Qibai
PP: 315-320
Abstract: According to the characteristic of magnetorheological fluid, fuzzy control method is proposed. Combined with the impedance match method, a new control strategy is applied to the control system. Then emphasis is put on the study about the input/output variables, the control rules and the logical reasoning of controller. At last, the experiment is carried out. The results denote that the active sound absorption method is feasible.
Keywords: mechanical design and theory; magnetorheological fluid; electric field; control; impedance
 
Title: Effect of tangential force on contact mechanics of thick-walled single cell body
Authors: XIE Fang, LIU Zuomin
PP: 309-314
Abstract: The effects of tangential force on the inner stresses and contact mechanics of high temperature sweating and self-lubricating thick-walled single cell body were analyzed using the ANSYS finite element software. The results show that: Tangential force has great influences on the stresses distributed on the contact surface, but it almost has no influence on its internal stresses, especially on the stresses distributed on the inner surface. On the contrary, the porosity has little effect on the stresses distributed on the contact surface. However, it influences the stresses distributed on the inner surface largely. Therefore, the existence of tangential force has little effect on the contact strength of high temperature sweating and self-lubricating thick-walled single cell body, but the change of porosity will greatly influence its contact strength.
Keywords: mechanical design and theory; thick-walled single cell body; tangential force; contact mechanics; stress distribution
 
Title: Influence of interference between rough points upon contact mechanism
Authors: MENG Fanming
PP: 303-308
Abstract: The interference between rough points upon the contact mechanism was analyzed by using ANSYS software. By use of parametric programming, surface roughness from the data file is put into a smooth matrix model with a number of discrete points, whose node numbers are consistent with those of roughness.Then the finite element analysis for the contact region was made. Numerical results show that the interference has an influence upon the stress and deformation of the rough surface, depending on the number and position of the contact point. Therefore, it is unreasonable that rough surface contact is decomposed into linear superposition of point contact due to neglecting the above interface. The proposed method may give a reference to study rough contact mechanisms.
Keywords: mechnical tribology; rough point contact; interference; finite element analysis; stress; deformation