Table of Content

10 May 2008, Volume 19 Issue 9

Previous Issue    Next Issue

Analysis of Temperature Field and Experimental Validation for 
Electrical Discharge Dressing and Truing of Electrical Diamond Grinding Wheel

Cai Lanrong，;Jia Yan;Hu Dejin

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (7443KB) ( )  

Related Articles | Metrics

A simulation model established by finite element methods using ANSYS software shows the distribution temperature field on the diamond wheel. The actual dressing experiment was conducted by the same EDM parameters as the numerical simulation model. And the wheel surface topographies before and after dressing was observed by optical microscope (KEYENCE VH-8000 Digital HD).The analyses show that the theoretical calculation results are consistent with those of experiments under the same experimental conditions. The simulation model is benefit to quality forecast, parameter regulation and optimization in the process of truing and dressing diamond wheel. It also helps to avoid that high temperature make diamond grain graphitization or the temperature is not high enough to remove the metal bond well. The simulation model can keep from the blindness to true and dress diamond wheel directly.

Study on the Trajectory Control of a 2R Horizontal Underactuated Robot

Fang Daoxing;Yu Yueqing;Zhou Gang;Ding Li

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (6430KB) ( )  

Related Articles | Metrics

Based on fuzzy control theory,an intelligent method of controlling the trajectory of a 2R horizontal underactuated robot with a passive joint was presented.Compared with the current methods,fuzzy control method does not rely on the dynamic model of the robot.Furthermore,it has good real-time and robustness characteristics.A 2R underactuated robot experimental setup and its control system were developed. Tracking control of several trajectories of this robot was achieved by experiments.The results show that the proposed method has high precision for trajectory tracking and good robustness.

Research on Nonlinear Dynamics of a Vibration-isolated Body

Chen Anhua;Gao Wei;Gao Yongyi 

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (3301KB) ( )  

Related Articles | Metrics

Seismic response characteristics and vibration stability of the body isolated by the resilient material with nonlinear stiffness and nonlinear damping were investigated herein.The nonlinear dynamics equation including nonlinear stiffness and damping was developed.The frequency response equation was derived and nonlinear dynamic response to a seismic excitation were analyzed by the method of harmonic balance.The effectness of nonlinear factors and vibration stability were studied.The conclusions of the paper are helpful to the accurate design and effect analysis of vibration isolators.

Meshless Analysis of the Substrate Temperature Evolution during Plasma Spray Process

Wu Shengchuan;Zhang Hai’ou;Wang Guilan

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (3437KB) ( )  

Related Articles | Metrics

This paper focused on establishing a sound 3-D heat transfer formulation based on the meshless local Petrov-Galerkin(MLPG) method and was used to solve transient heat transfers in the plasma spraying. The unknown temperature functions were approximated and constructed by a weight function, a polynomial basis and a set of non-constant coefficients. A quartic spline function was selected as the moving least-squares weight and test function. A penalty technique was introduced to enforce the essential boundary conditions. The effect of scaling parameters on numerical solutions was discussed in detail. The substrate temperature was computed using this formulation numerically. It is found that MLPG solutions can achieve better convergence and higher accuracy compared with FEM and are in good agreement with those from the experiments, suggesting that the MLPG is feasible and efficient and therefore applicable to heat transfer problems during the plasma spray process.

Research on Pointing of Face Gear by Enveloping Method

Li Zhengminqing;Zhu Rupeng 

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (5737KB) ( )  

Related Articles | Metrics

In order to produce face-gear drive, a face-gear drive with spur involute pinion was considered. The generation of the face gear was based on enveloping method. The equations of theoretic geometrical tooth surface and transitional surface of face gear were deduced and the phenomenon of pointing of face gear was analyzed. According to the analysis, the data of pointing are concluded and the engineering equation of pointing is gained. In the end, the feasibility of the theoretic results was received, by the experiments of face gear.

A Novel Design and Fabrication of MEMS Electrical Inertia Micro-switch

Yang Zhuoqing;Ding Guifu;Cai Haogang;Liu Rui;Zhao Xiaolin 

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (6949KB) ( )  

Related Articles | Metrics

A novel design of MEMS electrical inertia micro-switch was proposed. In the design, an elastic beam with holes was used as the fixed electrode, and a suspended thicker mass block with conjoined snake springs was used as the mobile electrode locating between the supporting layer and the elastic beam. This designed switch structure benefits the improvement of the sensitivity,the contact effect, and protects the switch against intensive shock damage. The micro-switch had been fabricated using cost-effective electroplating nickel and tested subsequently. The result indicates that the response time and the contact time of the micro-switch are about 0.40ms and 12μs respectively when 100g acceleration is applied, which shows relatively better sensitivity and contact effect. This result has an agreement with that of dynamics finite element contact simulation about the designed micro-switch.

Research on Grinding Residual Stresses Based on Thermo-mechanical Coupling

Ming Xingzu, ;Yan Hongzhi;Xiong Xianwen;Zhong Jue

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (6792KB) ( )  

Related Articles | Metrics

According to the principle of residual stress generation in grinding tooth，the mathematical models of basic parameters,force and thermal parameters of grinding tooth of spiral bevel gear were obtained by applying the thermo-elastic-plastic theory．Based on the 3D finite element model of single tooth，the method of small sub-step movement was used in processing loads of grinding，the indirect way was applied in thermo-mechanical coupling，and residual stresses of grinding tooth of bevel gear were simulated and analyzed by finite element．Many conclusions of the simulation are obtained．Firstly，compressive residual stresses are located on the tooth surface，tensile residual stresses are occurred in the tooth．Secondly，the values of residual stresses are changed according to a certain rule as varying the grinding condition and parameters．Its values are raised as increasing the grinding depth and wheel speed，while reduced as increasing the extended speed，and the values are more decreased in wet grinding than dry grinding．Finally，it is showed by experiments that the finite element thermo-elastic-plastic analysis of grinding residual stresses is effective，and the differences of grinding residual stress of spiral bevel gear are obtained by analyzing and comparing with one of column gear．These provide a foundation for the control of grinding quality of spiral bevel gear．

A New Method to Identify Minimal Cut Sets Using the Incidence Matrix of Petri Nets

Wu Ying;Xie Liyang;Li Jindong

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (3432KB) ( )  

Related Articles | Metrics

A method using incidence matrix of Petri net to identify the minimal cut sets(MCS) was proposed. This method can find CS according to the relationship among inputs and outputs implied in the incidence matrix, finally using Boolean absorption law, idempotent law, or prime law to get MCS.This method also shows its advantage when dealing with models containing repeatable events. The Visual C++6.0 code was developed and several examples were performed to test it. A naval vessels aerial defense system was also analyzed to show the process of this method and finally its validity was proved.

Mechanism Analysis and Treatment on Loss Corner Faults of Compressor Blades

Wang Jing, ;Wang Deyou;Han Qingkai

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (2805KB) ( )  

Related Articles | Metrics

For the loss corner faults of blades of second level in compressor, with comparion of blades’ natural characteristics and exciting sources in details, the faults mainly stem from fatigues for the 7th order and the 10th order vibrations. Dynamic optimized structure of blade and improved surface quality were studied to prevent the loss corner faults effectively. The state blades of the first level were also tried to be fixed in unequal distances to make blade vibration lower.

Snatch Collision Detection Algorithm Based on Normal Distance on Simplified Planes of Virtual Hand

Jin Yue;Hou Wenjun

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (3434KB) ( )  

Related Articles | Metrics

The paper researched snatching object with virtual hand in virtual assembly, and proposed a novel collision detection algorithm and theory based on normal distance on simplified planes of virtual hand according to the physical feature of snatching object.A tangent plane model was built,with which detect with each object of virtual hand to detect collision between virtual hand and accessories. The algorithm reduces the work on creating complex bounding box. F-V(face-volume) test was taken from the time complexity of algorithm and resource consuming.

Absolute Zero Calibration of the Base Points in Four-beam Laser Tracking Flexible Coordinate Measuring System

Wang Ting;Qiu Zurong;Li Xinghua

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (3311KB) ( )  

Related Articles | Metrics

In the laser tracking 3D coordinate measuring system, the self-calibration should be made before measurement that would take effect mostly on the result. But the precision of the self-calibration is not high. So, in order to enhance the calibration precision, especially give the absolute zero value of the system, a new method of calibrating the absolute zero point coordinates was proposed herein. First, a ordinary laser interferometer was employed to measure the displacement of the object mirror moved along the line, then the base coordinate and absolute zero value of this reference frame can be obtained. Considering the position distribution of base point and target point influence on the calibration precision of this system, an optimization distributions of the base point and the target points were analyzed and confirmed. After the simulation, the result shows that when the target points are distributed symmetrically relative to the base point, the measuring precision of the base point coordinates is much higher.

Fault Diagnosis on Multi-technique Oil Analysis Information Fusion Based on D-S Theory

Zheng Changsong;Ma Biao;Sun Xianlin;Ju Yinfang

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (2946KB) ( )  

Related Articles | Metrics

Through applying the D-S theory on the fault diagnosis research by the multi-technique oil analysis information fusion, the new methods for constructing the basic probability assignment was created to settle the key problem of the D-S theory. The fault symptom of the power-shift steering transimission(PSST) can be captured by using this method on the oil analysis of the reliability test, and this method can be used for engineering applications.


Algorithm and Application of Subordination Rule for Designing Complex Products

Wu Jinghua;Tang Wencheng;Xu Hongxiang;Ben Kecun 

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (4558KB) ( )  

Related Articles | Metrics

Subordination coding method is widely used in the enterprises which produce complicated products, yet, the coding rules are very complicated, and mistakes would be made with manual work. An automatic coding system based on Pro/Toolkit was displayed, which could code the designed products automatically. First, a series of subordination coding rule were listed according to national standard and some industrial standards, the rules were generalized, and the coding algorithm was designed. Then the process of constructing the system was described. Several modules are displayed: system structure, parameter visiting method, store rules in the product tree, re-coding means for the parts in the tree and parameters changing method. The system could be implemented with VC++6.0 and Pro/Toolkit, an example of coding for a product shows that all the parts can be coded correctly and efficiently with the designed system.

Knowledge Modeling and Management in Human-computer Collaboration for Scheme Design of Engineering Equipment

Peng Weiping;Wang Jinyao;Shen Lei;Wu Qingming 

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (4515KB) ( )  

Related Articles | Metrics

Human-computer collaboration knowledge for engineering equipment scheme design was classified into six types: historical knowledge, process knowledge, describable knowledge, assistant knowledge, control knowledge and human knowledge or experience. A complex knowledge model including above knowledge objects was presented based on object-oriented technique. This model can express static attributes,interrelations of complex knowledge objects, and their dynamic attributes, and can show human-computer collaboration relations. Three modes of storing knowledge objects in computer were also presented. These modes were by relation database, program and model file. Besides, issues of knowledge use in conceptual layer, logical layer and physical layer were discussed.

Research on Auto-production Line Fault Diagnosis Based on FNN

Wu Zongyan;Han Yu;Zhang Jianjun;Zhang Li 

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (3323KB) ( )  

Related Articles | Metrics

According to the failure characteristics of auto-production line, this paper adopted FNN as fault diagnosis method and designed a overall scheme for it.A diagnosis model of auto-production line based on FNN and data fusion technology was established.In order to test this model, this paper combined with a automatic super finishing line for ball bearing ring grinding, used the MATLAB neural network tool box to simulate and test the model which was established to diagnose the grinding wheel failure of the NC internal grinder on the auto-production line. The results show that this model can diagnose the faults rapidly, accurately and effectively.

Research on Milling Parameter Optimization Based on Control of the Workpiece Deformation

Tang Donghong,;Sun Houfang

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (2368KB) ( )  

Related Articles | Metrics

A milling parameter optimization method based on control of the workpiece deformation-by coupling neural network and genetic algorithm(GA) was proposed. In doing this, advantages of experimental design technique, artificial neural network and genetic algorithm were exploited in an integrated manner. Cutting experiments were designed based on uniform experimental design technique. A predictive model for deformation was created using a feed forward artificial neural network exploiting experimental data. Neural network model and analytical definition of material remove rate were employed in the construction of optimization problem. The optimization problem was solved by genetic algorithm. Additional experiments were conducted to validate the optimal values, the results show that the optimal parameter can decrease the deformation obviously. This indicates that the neural network model coupled with the GA can effectively utilized to find the best or optimum values of cutting parameter. 

Influence of Lead Angle on Elastic Deformation of Ball Screw 

Jiang Hongkui;Song Xianchun;Zhang Zuoying

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (4301KB) ( )  

Related Articles | Metrics

The mechanics model of a ball screw was developed considering the factor of lead angle,and the main curvature of the helical surface was deduced using differential geometry method, and the effect of lead angle on the elastic deformation
was analyzed.The result shows that the normal elastic deformation of ball screw decreases with the lead angle increases.

The Study on Boundary Conditions to the Effect of Mode Analysis in FEA

Li Zhixin;Li Xiaoqing;Chen Xuedong，;Chen Lumin

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (3803KB) ( )  

Related Articles | Metrics

During the period of carrying on the mode analysis, how to deal with the boundary conditions will influence the accurate analytical result directly. The theory discussion is carried on in the paper. Two typical boundary conditions were carried on the structure and the mode analysis was implemented in detail, too. There have much more different between them. The test mode was carried on, through which we find the importance of boundary conditions will influence the result furthermore. Through the reanalysis and the compare between the test and the reanalysis results, the frequencies and the accurate boundary conditions was recognized.

Change of Natural Frequency for Gear During Strengthening and Damaging

Lu Xi;Zheng Songlin;Li Pingping 

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (6563KB) ( )  

Related Articles | Metrics

The dynamic response frequency change of single tooth bending for automobile transmission gear was investigated during the process of damaging and strengthening. The experimental results show that the natural frequency varies with damaging and strengthening. The natural frequency decreases slowly along with damaging and descendes 3Hz when the single tooth is fractured. On the contrary the natural frequency may be increased to near 2Hz when the single tooth arrives to optimal strengthened effect. The reason of the natural frequency change was primary explained in microstructure. These investigation results will provide new technical base for estimating the damage or strengthening by the dynamic response frequency change.

Weld Line Performance Analysis of the Welding Stainless Steel Tube Based on Tube Hydraulic Bulging Test

Xu Yan;Gao Lin;Li Shuanggao

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (7686KB) ( )  

Related Articles | Metrics

From the point of the whole performance, tube hydraulic bulging test was used to estimate the weld line performance of the stainless steel in tube hydroforming. With the help of laser, different states of the weld line was achieved and analyzed. Then, a standard of estimating the weld line was constructed based on FEM and test. Using tube hydraulic bulging test to test the weld line is simple and strong that it is a good guide to produce the welding stainless steel of good quality. 

Research on Flexibility Mechanism of Magnetron Granular Polishing Head


Zhang Xian;He Yang;Ji Shiming;Wang Yangyu;Zhao Zhangfeng

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (5280KB) ( )  

Related Articles | Metrics

A new flexible free-form surface polishing device was proposed to improve polishing efficiency of mold free surface by changing magnetic field intensity to change the magnetic force between ferromagnetic granular in device, which can achieve the adjustable flexibility in real-time. The relationship between nonmagnetic induced shear capacity and the magnetic induced shear capacity of magnetron granular was established based on Mohr-Coulomb’s failure criterion, magnetic dipole and elasticity theory. And the shear capacity model of ferromagnetic granular in an ideal state was also established. Through the analysis of experimental data, combined with shear capacity model, the shear force model of ferromagnetic granular can be obtained in the role of the magnetic field. The results show that in magnetic field, the shear capacity of ferromagnetic granular includes nonmagnetic induced shear capacity, anti-shearing force, magnetic induced shear capacity, and its anti-shearing force. The magnetic shear capacity and anti-shearing force is related to magnetic field and the volume of ferromagnetic materials.

A Completed Adaptive NURBS Curve Interpolator Algorithm

Li Jiangang;Zhang Tinghua;Li Zexiang;Liu Guanfeng

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (4104KB) ( )  

Related Articles | Metrics

A completed adaptive interpolator was developed for non-uniform rational B-spline (NURBS) curves interpolation herein. In the proposed interpolator, both the chord accuracy and the acceleration/deceleration capability of machine tool were considered. Three modules, adaptive-feedrate adjustment, acceleration/deceleration disposal and feedrate modification, were applied to deal with the acceleration/deceleration around the feedrate sensitive sharp corners, and finally a satisfactory result is achieved. A case study was provided to evaluate the feasibility of the developed interpolator at last.

Condition Detecting and Trouble Diagnosis Technology on Centrifugal Compressor

Shi Junxia;Yang Zhaojian;Li Chunsheng

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (3425KB) ( )  

Related Articles | Metrics

According to the compressor’s structural features, we selected the pressure of the lubricating oil, the temperature of the bearing, the landscape orientation vibration and displacement of the shaft for sensitive parameters to complete the on line detection, and we also gave the threshold value about the alarm and interlock in order to stop the compressor running as those signals were out of limit. The signals of vibration and displacement of the shaft were collected and processed. Depending on the locus of journal center, spectrum characteristics and the phase characteristics, the trouble diagnosis was made, and the prediction maintenance was applied , so as to ensure the compressor working safely and reliably,thus improves the availability factor of the equipment and the modern management.

Analysis of Adjusting Magnetic Field and Efficiency of Electric-magnetic Continuously Variable Transmission

Luo Yutao;Yu Hao

2008, 19(9):  0-1054. 

Asbtract ( )   PDF (5455KB) ( )  

Related Articles | Metrics

The working principle and adjusting the magnetic field principle of the system of electric-magnetic continuously variable transmission(EMCVT) were analyzed in detail herein. By the 2D FEM and 3D FEM, the magnetic field on EMCVT and the effect of adjusting magnetic field on the air-gap magnetic field was studied. And according to the effect of adjusting magnetic field on the air-gap magnetic field, the efficiency of EMCVT was also studied, so as to prepare for the development of the control strategy and control system.

Study on Knuckle Angle Influence on Smooth Level of Same Diametral Axis Formed with Multi-wedge Cross Wedge Rolling(MCWR)

Zhao Jing;Shu Xuedao;Hu Zhenghuan

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (4175KB) ( )  

Related Articles | Metrics

The transition zone shape is oblique step formed with knifing stage of side wedge. It was analyzed in different knuckle angle by FEM simulation and rolling test. The rule of knuckle angle value influence on smooth levels of surface in forming the equal diameter axis with MCWR was obtained. This result has important guideline for forming long-axle parts with MCWR.
cross wedge rolling;multi-

Experimental Study on Hydrostatic Extrusion Processes of AZ31 Magnesium Alloy

Zhao Zude;Wang Shaochun;Hu Chuankai;Kang Feng;Shu Dayu

2008, 19(9):  0-1057. 

Asbtract ( )   PDF (5682KB) ( )  

Related Articles | Metrics

Focusing on the problem that no national equipment and its costly price for hydrostatic extrusion of magnesium alloy, a set of experimental facilities were developed, which can be applied to hydrostatic extrusion of magnesium alloy and suit for ordinary home press in low cost.Several key technical matters such as high pressure mould, control in extruding speed of magnesium alloy silk , self-control in temperature in the process of extruding and hot sealing in heavy pressure were solved. The regression equations showing number relations of temperature and specific fluid pressure under the conditions of different extrusion ratios were achieved by means of least square method to fit curves. Tests of hydrostatic extrusion process were finished by means of 3150kN press, and AZ31 magnesium alloy silks with better mechanical property than rolling one’s are obtained. 

Research on Assist Characteristics of Electric Power Steering System

Chen Long;Yuan Chaochun;Jiang Haobin;Lu Haiyan

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (3273KB) ( )  

Related Articles | Metrics

Based on analysis of affecting the assist characteristics,a model for steering torque of vehicle was built up. The relation between steering torque and load of vehicle was ensured through dynamics simulation and electric power steering test bed. The new assist characteristics of electric power steering system was made sure under the effect of load of vehicle,speed and steering torque. The experimental and simulation results show that the characteristics of controller designed under new assist characteristics are better.

Thermodynamics Simulation of a New Hybrid Compressed-air and Fuel Engine Concept

Fang Qinghua;Liu Hao;Chen Ying;Tao Guoliang

2008, 19(9):  0-1057. 

Asbtract ( )   PDF (3966KB) ( )  

Related Articles | Metrics

A new hybrid compressed-air and fuel engine concept was proposed, which can work by both compressed-air powered engine mode and internal combustion engine mode. The new hybrid engine was modeled using ideal thermodynamics cycles, and the simulation analysis was made in the indicated mean pressure as well as other performance parameters. The simulation results show that the indicated mean pressure and other important performance parameters are approximate to those of the traditional internal combustion engine, and switch between the two engine modes is smooth. Results show the feasibility of the new hybrid compressed-air and fuel engine concept in achieving fuel economy and emission reduction. 

Simulation Analysis of Inner Force Characteristics of Car Body
Thin-walled Beam Structures Subject to Lateral Impact

Su Chengqian;Lü Zhenhua

2008, 19(9):  0-1133. 

Asbtract ( )   PDF (7861KB) ( )  

Related Articles | Metrics

Inner force characteristics are important for car body crashworthiness analysis. Using a new numerical algorithm for thin-walled beam inner forces based on shell element model, a method for analysis of structural inner force response characteristics under lateral impact was presented and numerically demonstrated with some cylinder impact cases. Variation and transfer of thin-walled beam inner forces, moments, power and energy were analyzed in details. Two elementary crash types, cylinder impact to structure and structure impact to cylinder, belong to diffusion and convergence energy transferring modes respectively. Main supported load and major energy path during impact were determined by structure type and load case. The impact response characteristics of thin-walled beam were revealed, which provides some important information and method for structural evaluation and design.