Table of Content

25 June 2010, Volume 21 Issue 12

Previous Issue    Next Issue

Implementation of NURBS Interpolation Based on Biarc Numerical Algorithm 

SHI Xu-Guang, XU Bu-Gong

2010, 21(12):  1387-1391. 

Asbtract ( )   PDF (3613KB) ( )  

References | Related Articles | Metrics

As the key technology of modern numerical control

system, complex trajectory NURBS interpolation technology catches close attentions from the manufacturing industry and academia all along. This paper presented a new method building NURBS interpolation technology platform from the viewpoint of theoretical deduction of NURBS mathematic relation and numerical algorithm of biarc. And some numerical methods to reduce speed variation were investigated to fulfill develop purpose. Finally, the experiments were carried out to verify the research feasibility. 

Study on Kinematic Relations for Capillary and Wire Kink Points in Wirebonding Loops

ZHOU Hong-Jun, HAN Lei

2010, 21(12):  1392-1397. 

Asbtract ( )   PDF (4571KB) ( )  

References | Related Articles | Metrics

The video of wire bonding was divided into continuous image sequences. The trajectories of capillary and wire’s kink points were obtained by phase correlation algorithm and chord-to-point distance accumulation technique respectively. The velocity distributions and rotation angles of capillary and kink points to the first bonding were calculated according to the trajectories. The correlation rules of capillary and wire movement were obtained by analyzing their rotation angles and velocity distributions in wire bonding. For the capillary falling stage is circular motion, the circle center positions of locus circles were obtained by fitting the falling stage trajectories. The corresponding relation between circle center positions and wire profiles was found. The proposed method provides valuable reference for further studying the dynamics characteristics of the capillary and wire in the wire bonding looping formation.

 

Identification and Compensation for Volumetric Errors of CNC Machine Tools Based on SVM

TUN Xiong-Biao, TAO Xin-Hua, HE Zhen-E, FU Jian-Zhong

2010, 21(12):  1397-1400. 

Asbtract ( )   PDF (2980KB) ( )  

References | Related Articles | Metrics

A novel method of identification and compensation volumetric errors for machine tools based on SVM was presented herein. Training and learning the error samples and optimizing the SVM parameters, the volumetric error models were obtained for compensation. By laser sequential step diagonal measurement, the volumetric errors were identified and compensated. The experimental results illustrate that the SVM model is adaptive to forecast volumetric errors of machine tools.

Comparing the neutral network model, the SVM model of volumetric error is more precise and quick. Using the SVM volumetric error model, it is succeeded to enhance the precision for CNC machine tools.

Semi-active Control of Landing Gear Shimmy Based on Magneto-rheological (MR) Damper

CHEN Da-Wei, GU Hong-Bin, TUN Dong-Su

2010, 21(12):  1401-1405. 

Asbtract ( )   PDF (3938KB) ( )  

References | Related Articles | Metrics

In order to study the semi-active control of landing gear shimmy based on MR damper, firstly function expression of the MR damper equivalent damping coefficient with voltage and amplitude was set up. Secondly, the mathematical model for semi-active control of landing gear shimmy was constructed and maximum energy dissipation approach was proposed to suppress shimmy based on MR. Finally, the critical velocity of shimmy varying with the vertical force during taxing was investigated in different caster lengths.The simulation results show that the performance of MR to suppress shimmy is greatly superior to hydraulic shimmy damper during taxing. And MR suppresses shimmy completely and exhibits good robustness about some system parameters.

Study on Multi-feature Analysis of Engine Wear Based on Oil Denoised Data

XU Qi-Ku, HU Ze-Yin, XU Hou-Chang

2010, 21(12):  1405-1409. 

Asbtract ( )   PDF (3534KB) ( )  

References | Related Articles | Metrics

To advance efficiency and pertinence in monitoring engine wear condition applying oil analysis, oil spectrometric and direct-reading ferrography data denoised by wavelet packet was used to extract three boundary features. In combination with centroids feature obtained through K-means clustering, centroid-boundary multi-feature analysis was established to monitor wear state of main friction pairs of certain engine, and the decision table about wear condition was formed. The result shows that compared to the decision table obtained by traditional three-line method, the partition of wear state based on multi-feature analysis is more detailed, accurate and instructionally significant. The identification efficiency for wear state increases by one time. Moreover, the

study of the relativity between oil spectrometric signals indicates the abnormal wear of piston ring friction pairs, which further confirms the pertinence and availability of multi-feature analysis. 

Analysis of Vibration Signals of Piston Pin in Diesel Engine Based on Higher Order Cyclostationarity

JIA Tian, WANG Xin-Qing, XIAO Yun-Kuai, LIANG Sheng

2010, 21(12):  1410-1414. 

Asbtract ( )   PDF (2275KB) ( )  

References | Related Articles | Metrics

Higher order cyclostationarity of the vibration signals of the piston pin of a diesel engine was studied, and a novel feature extraction method of diesel engine’s piston pin’s wear fault based on the higher order cyclostationarity was proposed herein.Vibration signals of piston pin were analysed with the cyclic bispectrum, the frequency component’s distribution of the vibration signals in the cyclic

bispectrum was studied, and a new global search method was proposed.The cyclic bispectrum characteristic planes whose average modulus values can reflect the wear clearances of the piston pin were found as fault features. The results demonstrate the effectiveness of the cyclic bispectrum method, and 5 cyclic bispectrum planes connecting with the wear clearances of the piston pin are found in the vibration signals’ cyclic bispectrum and the average modulus values of these planes can be extracted as the feature of the crankshaft bearing wear fault of diesel engine.

Cathode Design in Electrochemical Machining of Cavities among Blades of Closed Integral Impeller

WANG Jun, DIAO Jian-She, LIU Chen, XU Jia-Wen

2010, 21(12):  1414-1417. 

Asbtract ( )  

References | Related Articles | Metrics

An organic combination of numerically controlled electrochemical machining(NC-ECM) and numerically controlled electrical discharge machining(NC-EDM) is useful to solve the problem of how to machine closed integral impellers.NC-ECM is the key step to increase the process efficiency,and the cathode design is the key technique of NC-ECM.Taking the numerically controlled electrochemical machining of a 3D-flow composed impeller as an example,a method of cathode design was put forward herein.Machining experiments were carried out and the machining allowance of the integral impeller can maintain 0.5～0.7mm,meeting the precision requirements.

Analysis of New Relieve Valve Metal Crinkle Diaphragm Based on Bond Graph

DI Hua, ZHONG Hua-Yong, SUN Yun-Dong, LIU Zhong-Hua, DIAO Ying-Chun, DIAO Han

2010, 21(12):  1418-1423. 

Asbtract ( )   PDF (1795KB) ( )  

References | Related Articles | Metrics

The press variation loaded on metal crinkle diaphragm was

studied based on analysis of the new relieve valve operation process. The bond graph described the relieve valve dynamic feature was presented to set up the state space equation, from which the simulation results were calculated based on the Lunge-Kutta methods to express that the crinkle diaphragm will be loaded 21MPa at the beginning of the relieve press procedure,and the press will be 3.43MPa after 0.06s,the

valve core space will be 3.165mm after 0.08s. A crinkle diaphragm solid finite element model was built up, and stress and deformation with the maximal press 21MPa

 was computed, and creep process was simulated to estimate the diaphragm invalidation or not according to the Norton theoretic model.The experimental results are better conformability with the simulation ones. The conclusion expresses that the new crinkle diaphragm will be plastic deformed when loaded on 21MPa, and creep after long term higher press. But the diaphragm will be also available after plastic deformation, and the

creep diaphragm deformation and stress will be stable loaded with 21MPa after 1.4256×106s,and also work normally.The simulation method offers good help to the new relieve valve design.

Structural Optimum Design and Motion Simulation of Erected Circular Medicine-chest

ZHANG Zhi-Jiang, YUAN Chao, LIU Xiang-Quan, LIU Yang

2010, 21(12):  1423-1429. 

Asbtract ( )   PDF (5225KB) ( )  

References | Related Articles | Metrics

In an erected circular medicine-chest,mechanical structure and working principles were analyzed,noninterference moving condition of reserving medicine basket was discussed with different phases,optimum function of chain drive based on noninterference moving condition was ascertained and solved by using Matlab,the minimum circular radius of reserving medicine basket and design parameters of chain drive were finally obtained.For keeping reserving medicine basket horizontally running, guides of balance bar were rationally located.The motion simulation model was set up with using UG and ADAMS. Motion simulation was carried out to prove the success of optimum design based on the noninterference moving condition of reserving medicine basket.The whole system development has been completed and applied in the outpatient-service pharmacy.It runs well now. 

Determination of Integrated Priority Ratings of Customer Requirements in Product Planning Based on Balanced Scorecard

LI Yan-Lai, LUO Xin-Gang, HAN Yi, TAO Jian-Meng

2010, 21(12):  1430-1434,1440. 

Asbtract ( )   PDF (4000KB) ( )  

References | Related Articles | Metrics

Determination of the integrated priority ratings of customer requirements in a product planning house of quality was investigated for new product development.Firstly,according to the competitive evaluations and complementary preference matrixes of customer requirements for the selected customers,a model determining the priority ratings of customer requirements corresponding to every one of the selected customers was built and resolved by using Lagrange function,and then the fundamental priority ratings of customer requirements from the angle of customers’ view were determined by using group decision-making approach. Secondly,based on the integration of balanced scorecard and analytical hierarchy process,the priority ratings of customer requirements from the angles of no-customer views were determined. Lastly, based on a combination of the priority ratings of customer requirements from the angle of customers’ view and the priority ratings of customer requirements from the angles of no-customer views, the integrated priority ratings of customer requirements were determined. A case study was provided to illustrate the applications of the proposed method. 

Chinese Logistics Industry International Competitiveness Evaluation Based on Fuzzy Analysis Method

LI Chi, XUE Dong-Hui

2010, 21(12):  1435-1440. 

Asbtract ( )   PDF (3963KB) ( )  

References | Related Articles | Metrics

Based on theoretical analysis, questionnaire was designed according to logistics industry’s factors. The questionnaires’results were analyzed by data analysis methods to establish Chinese logistics industry international competitiveness index system innovatively.Then fuzzy analysis method was introduced to Chinese logistics industry international competitiveness evaluation,and the results were given.The results show that the entire international competitive ability of Chinese logistic industry is relatively

poor,but because the influence of infrastructure construction and international level

factors on the competitive ability is very strong,we can increase our international competitive ability from above factors.

Tobacco Packaging Scheduling Technology Based on Manufacturing Resources Dynamic Combination

DING Lei, WANG Ai-Min, NING Ru-Xin

2010, 21(12):  1441-1446. 

Asbtract ( )   PDF (4243KB) ( )  

References | Related Articles | Metrics

A tobacco packaging scheduling algorithm was put forward to solve problem feeder-packer-brand’s flexible constraint in the tobacco packer production line based on dynamic manufacturing resource composition.The algorithm included the rules and the heuristics of tobacco packaging scheduling.The scheduling algorithm was divided to solve the problem of manufacturing resources dynamic combination.The data structure of order was defined which was based on the relationship between work orders and scheduling plan. The way to dynamic packer composition and stopping at same time on machine group algorithm considering the work colander were proposed. The tobacco packaging scheduling system is developed and used in practice.

tobacco packaging scheduling;dynamic manufacturing resource composition;heuristic

Consistency Maintenance of Multidisciplinary Collaborative Product Design

CHEN Liang, WANG Wei

2010, 21(12):  1447-1452,1468. 

Asbtract ( )   PDF (4712KB) ( )  

References | Related Articles | Metrics

Aiming at the characteristics of multidisciplinary collaborative product design, such as multiple domains, multiple views and dynamic nature, a study of relating and coordinating multiple discipline view models was made.A multidisciplinary constraint and relation net model merging function,behavior and structure was put forward,the structure relation set and the semantic relation set were defined.The principles and methods to realize consistency maintenance among multiple discipline view models were

presented by means of the methods synthetically using relation,constraint,semantics reasoning and project management to make the static and dynamic coordination among multiple discipline view models.And a reducer was illustrated to validate the proposed methods.

Numerical Simulation of Flow Field Dynamics Characteristics for Twin-screw Pump

TANG Qian, ZHANG Yuan-Xun, GAO Zhan

2010, 21(12):  1453-1457. 

Asbtract ( )   PDF (2288KB) ( )  

References | Related Articles | Metrics

A new kind of highly effective, sealing superiorly and involute-modified twin-screw pump was proposed, compared with cycloid twin-screw pump and based on limited volume method,the numerical simulation models of two kinds of pumps were established. By analyzing their pressure fields, velocity fields and so on basic rules, the twin-screw pumps flow channels’ volumetric efficiency were obtained. The research indicates that the flow channel pressure progressively increases along with the sealed chamber, the peer pressure is in the tendency of reduction as a result of leakage; the eddy flow phenomenon exists in the flow channel spiral flute, the meshing area is mixed intensely, the negative axial velocity exists in the contact area of rotor and pump cover’s wall surface and the meshing area which are the main leakage areas. Involute-modified twin-screw pump volumetric efficiency is relatively high, with superior sealing performance. The research findings will provide the theory basis for the later screw pump’s development design.

PSO-based Blind Deconvolution Algorithm and Its Application in Bearing Fault Detection by Acoustical Analysis

CHEN Yi, WU Xing, CHI Yi-Lin, WANG Yu

2010, 21(12):  1457-1461. 

Asbtract ( )   PDF (2845KB) ( )  

References | Related Articles | Metrics

In complex mechanical sound field, it is very difficult to set the

length of separation filters of blind deconvolution algorithm which generally leads to the separation results uncertain. Here,an improved blind deconvolution based on PSO algorithm was proposed. The reciprocal of maximize kurtosis was used to be as fitness function, and the optimal length of the separation filters can be selected by the PSO algorithm. With the help of the enhancement, good results can be obtain. Results of simulation and acoustical signals of faulty rolling bearings measured in actual environment were presented to demonstrate that the method is availability.

Reliability Analysis of Alumina-based Ceramic Cutting Tool's Wear Life by Saddlepoint Approximation

JIN Ya-Juan, ZHANG Xi-Min, ZHANG Yan-Lin

2010, 21(12):  1462-1465. 

Asbtract ( )   PDF (2981KB) ( )  

References | Related Articles | Metrics

Under continuous cutting conditions, the reliability of alumina-based ceramic cutting tool’s wear life with abrasion wear was discussed extensively.An ultimate state equation of alumina-based ceramic cutting tool’s wear life was proposed according to stress-strength interference theory.Based on the premise that the probability distribution of random parameters has been known, the fracture toughness

 K_IC and the hardness H which obeys Weibull distribution were transformed into normal distribution by means of the equivalent normal distribution method, then the reliability of alumina-based ceramic cutting tool’s wear life was analyzed by saddlepoint approximation method. The probability density function and cumulative distribution function of the ultimate state equation were accurately and quickly obtained by way of saddlepoint approximation,as a result, the saddlepoint approximation method was proved accurate with high computing speed in comparison with the Monte-Carlo method. Therefore, the application of the saddlepoint approximation method developes the reliability analysis theory of alumina-based ceramic cutting tool’s wear life.

Maximum Entropy Prior Information Solution Based on Second Moment and Its Application in NC System Reliability Assessment

LING Guang, DAI Yi, LI Xi

2010, 21(12):  1466-1468. 

Asbtract ( )   PDF (345KB) ( )  

References | Related Articles | Metrics

The paper studied NC system reliability assessment using Bayesian theory.We gave a general analytical solution of maximum entropy of Weibull prior distribution based on second moment restrictions.Combining NC system life data,the robustness of the Weibull prior distribution was discussed.Studies show that it fits NC system reliability assessment to solve the two-parameter joint prior distribution using maximum entropy principle.

Centroid Measurement System and Error Analysis Based on Three-point Supported

ZHONG Jiang, DIAO Zhang-Feng, JIAO Xin, ZHANG Xian

2010, 21(12):  1469-1472,1476. 

Asbtract ( )   PDF (3593KB) ( )  

References | Related Articles | Metrics

A centroid measurement system of complex mechanical products was established based on three-point platform supporting reaction theory. The sources of error were analyzed,a conclusion that the dominant errors of the measurement system primarily steamed from the measurement errors of pressure transducers and the displacement error of lift putters can be reached. A formula of calculating the theoretical error was presented after a detailed study of the influence of system structure parameters and system

random error over the centroid measurement. The experimental results show that the curves of analytical and experimental centroid altitude are coherent, especially, when the roll angle of supporting platform is large than ten degree, the result tends to the same.

Key Techniques of Large-Scale Space Angle Measurement Based on Common Optical Reference

TAO Jiang-Wei, ZHANG Guo-Xiong, QIU Jie-Rong, HU Wen-Chuan

2010, 21(12):  1473-1476. 

Asbtract ( )   PDF (1263KB) ( )  

References | Related Articles | Metrics

A method for measuring the angles in large-scale space based on a common optical reference was proposed. By setting up the common optical reference in large-scale space within several to tens of meters, by combining vision inspection technique and image processing technique, the angle among the elements separated at a large distance was determined in a relatively simple way by measuring the angle among reference and each element. In addition, the ways of forming a common optical reference were analyzed. Based on the proposed principle, a practical example of angle measurement formed by two axes separated at a distance of 7m was shown. 

Positioning Study of the Working Table Based on MRF Locking Damper

TU Xiao-Fen, MA Wen-Beng, CHENG Ling-Li

2010, 21(12):  1477-1480. 

Asbtract ( )   PDF (3088KB) ( )  

References | Related Articles | Metrics

A MRF locking damper herein based on MRF adopted novel horizontal structure. It can solve the contradiction between the seal of MRF and the larger initial frictional damping force for the vertical structure. Furthermore it has flexible damping and can lock the working table without impact,which reduces the impact brought by traditional locking method and the vibration caused by the linear electric motor’s driving. It is successfully applied to Nano-CMM and makes sure that the resolution of the working table achieves 5nm in X,Y direction and the positioning steady-state fluctuation is improved to 5nm from primary 20nm. 

Analysis on Self-compressibility of Sealing Materials under High Pressure in Deep-sea

ZHOU Bo, CHEN Jia-Wang, GU Lin-Yi

2010, 21(12):  1481-1484. 

Asbtract ( )   PDF (2914KB) ( )  

References | Related Articles | Metrics

The deep-sea experimental instruments' sealing performances are influenced by the self-compressibility under high pressures.The authors deduced the formula of calculating the axial compression ratio,and did the axial compression experiments on the following three kinds of sealing materials: fluorine rubber, silicone rubber and nitrile butadiene rubber, which shows the self-compressibility of sealing materials is less than 6% under the deep-sea high pressure (10 000 m means 100MPa). Therefore the principles of designing sealing structures at atmospheric pressure can be adopted(sealed slot, O-ring selection, etc.);however,the O-ring equivalent diameter should be appropriately enlarged by 10% for the sake of security.

Simulation and Experimental Research on a New Technique Named Equal Channel Angular Extrusion and Twist Prepared by Pure Aluminum 

XUE Ke-Min, TUN Zhan-Li, LI Ping, WANG Xiao-Xi, GU Jian-Lei

2010, 21(12):  1485-1489. 

Asbtract ( )   PDF (3605KB) ( )  

References | Related Articles | Metrics

In order to improve the insufficiency of ECAE,another super plastic deformation method(SPD)—TE was combined to create a new technique process—ECAE-T,which was first proposed. The finite element simulation about pure aluminum deformation during these three techniques was carried out by simulation software DEFORM-3D at room temperature. The distribution of effective strain and stress on the sample during ECAE-T were mainly obtained. The results show that there are two main deformation zone in the sample during ECAE-T and the effective strain is higher than ECAE and TE. The experiments about pure aluminum at room temperature during ECAE and ECAE-T were carried out using our own die. The results by simulation and experiments are extraordinary consistent. The optical organization after ECAE-T one pass is elongated much longer and smaller. The technique of ECAE-T is proved as a more excellent SPD method with the results of simulation and experiments. 

Simulation and Research of Starting Conditions of ISAD at Normal Temperature

WEI Chang-He, WANG Zhong, TANG Ting, HUANG Cheng-Hai

2010, 21(12):  1490-1495. 

Asbtract ( )   PDF (4177KB) ( )  

References | Related Articles | Metrics

According to the starting conditions at normal temperature (18℃) of diesel engine which is in the use of ISAD technology, this paper gave the working model of diesel engine and ISG electromotor. It obtained the torque and power that the ISG electromotor should provide on the starting conditions. Then it made the simulation computation to the starting process. Finally, through the bench test of the ISG electromotor dragging diesel engine under the different voltages, the confirmation and the analysis

were carried out to verify the simulation results. As a result, the bench test and simulation can be quite good tallied. It shows that in the use of ISAD technology,when the battery voltage of 36V, 48V, 60V, the diesel engine may be dragged to meet the speed requirements. 

Research on Optimal Control of Twin Clutch Engagement Pressure for Dual Clutch Transmission

LI Yu-Ting, DIAO Chi-Guo, ZHANG Dong-

2010, 21(12):  1496-1501. 

Asbtract ( )   PDF (4248KB) ( )  

References | Related Articles | Metrics

The coordinated control of the dual clutch has always been a hot issue in the DCT control system's research. Based on the running principles and simplified structure of DCT, the dynamics models in the vehicle launch and gearshift process were built. Considering the two performance indicators of the jerk and slipping friction work, linear quadratic optimal control strategy was used to obtain the pressure of

 the twin clutches. Especially, a specific ratio of the pressure change rate between the two clutches was introduced to simplify the optimization during the vehicle gearshift process. Meanwhile, the control effects of the different weighted factors and coefficients of

the two clutches pressure were compared through simulation. The results show that the linear quadratic optimal control strategy can resolve the problem of clutch pressure control in the vehicle launch and gearshift process.

A Modified Vehicle Safety Distance Model Adapting to Driver Individual Characteristics

BIAN Meng-Yuan

2010, 21(12):  1502-1506. 

Asbtract ( )   PDF (3374KB) ( )  

References | Related Articles | Metrics

The influence on safety distance model from the driver states was analyzed by using compositive weighting method, and a modified model based on modification factor was proposed to take consideration the effects of driver characteristics. Simulations have been done for car following and collision warning in different driving situations, which demonstrates the flexibility of the new algorithm of vehicle safety distance. And the conclusion is also obtained that the effect of the driver individual characteristics are mainly focused on the warning safety distance, and little on critical safety distance. 

A New Method of Simplified Modelling for Atuomobile Frontal Impact Sled

DONG Li-Jiang, LI Guang-Yao, CHEN Chao, GAO Hui

2010, 21(12):  1507-1511. 

Asbtract ( )   PDF (3459KB) ( )  

References | Related Articles | Metrics

A new method was presented by using sled impact test and substituted whole car impact test and this method was used to validate crashwothiness of whole car. Based on impact energy absorb analysis,selection method of parts composing sled model was presented.These parts included engine and drive sistem, suspension system, wheel, under body and so on. The results of simulation and crash test indicate that front longitudinal beam deformation and body acceleration curve of the sled model has good consistency with that of whole car crash. The sled model reduces simulation time and test cost heavily.