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A Method for Identification and Compensation of Machining Errors of Digital Gear Tooth Surfaces

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武汉理工大学学报 2006年第S3期28卷 1135-1139页

作者： WANG Fulin~1 YI Chuanyun~2 CHEN Jing~1 YANG Shuzi~2 (1.College of mechanical and Automotive engineering,Hunan University,Changsha 410082,China, 2.School of mechanical science and engineering,Huazhong University of science and Technology,Wuhan 430074,China) College of mechanical and Automotive engineering Hunan UniversityChangsha 410082China School of mechanical science and engineering Huazhong University of Science and TechnologyWuhan 430074China

In order to generate the digital gear tooth surfaces(DGTS)with high efficiency and high precision,a method for identification and compensation of machining errors is demonstrated in this *** errors are analyzed directly from the real tooth *** topography data of the part are off-line measured in the post-process.A comparison is made between two models:CAD model of DGTS and virtual model of the physical measured *** a matching rule is given to determine these two surfaces in an appropriate *** developed error estimation model creates a point-to-point map of the real surface to the theoretical surface in the normal direction.A“pre-calibration error compensation”strategy is *** processing the results of the first trail cutting,the total compensation error is predicted and an imaginary digital tooth surface is reconstructed. The machining errors in the final manufactured surfaces are minimized by generating this imaginary *** example of ma- chining 2-D DGTS verifies the developed *** research is of important theoretical and practical value to manufacture the DGTS and other digital conjugate surfaces.

关键词： digital gear tooth surfaces(DGTS) machining error topography measurement error analysis error compensation

Multi-View Point Clouds Registration without Feature Extraction for Use in Reverse engineering of CAD Models

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Computer Aided Drafting,Design and Manufacturing 2001年第2期11卷 46-52页

作者： Huang Xiaoping,Xiong Youlun School of mechanical science and engineering Huazhong University of science and Technology, Wuhan 430074, China Reverse engineering School of mechanical science and engineering Huazhong University of science and Technology Wuhan 430074 China

For reverse engineering a CAD model, it is necessary to integrate measured points from several views of an object into a common reference frame. Given a rough initial alignment of point cloud in different views with point-normal method, further refinement is achieved by using an improved iterative closest point (ICP) algorithm. Compared with other methods used for mult-view registration, this approach is automatic because no geometric feature, such as line, plane or sphere needs to be extracted from the original point cloud manually. A good initial alignment can be acquired automatically and the registration accuracy and efficiency is proven better than the normal point-point ICP algorithm both experimentally and theoretically.

关键词： reverse engineering iterative closest point algorithm registration.

Planetary scroll surface polishing method for aluminum wheel hub

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Journal of Shanghai University(English Edition) 2010年第5期14卷 343-348页

作者：陈义吴昌林 School of mechanical science and engineering Huazhong University of Science and Technology

Instead of manual polishing work for aluminum wheel hub （hub） surface, a new planetary scroll surface polishing method based on the rotation and revolution of hub in abrasives is presented in this paper. Since conventional barrel rotation polishing mode is unsatisfactory, shorter polishing period and lower energy consumption are expected. The surface polishing mechanism of the proposed method is ghen introduced. The influence of cutting velocity, cutting angle, abrasive on surface polishing quality and efficiency, as well as the correlation of the revolution velocity and the rotation velocity of hub are discussed. Experimental results show that high surface polishing quality and efficiency can be achieved with the new polishing method implying that a dustless clean working environment is realized.

关键词： aluminum wheel hub scroll polishing

Wafer level bonding using localized radio-frequency induction heating

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science China(Technological sciences) 2010年第5期53卷 1252-1257页

作者： CHEN MingXiang1,2,LIU WenMing1,2,XI YanYan1,2,LIN ChangYong1,2 & LIU Sheng1,2 1 School of mechanical science & engineering,Huazhong University of science and Technology,Wuhan 430074,China 2 Division of MOEMS,Wuhan National Laboratory for Optoelectronics,Wuhan 430074,China 1. School of mechanical science & engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of MOEMS Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

A wafer level bonding technique by localized induction heating has been developed and demonstrated in this paper.A suitable fabrication process scheme has also been established for the localized induction heating and *** takes only about 20 seconds to complete the bonding *** temperatures of solder loops and the central area of solder loops are above 300°C and below 70°C,*** to the solder reflow,robust and hermetic glass wafer bonding is accomplished,and the average tensile strength is 6.42 ***-heated or over-heated bonding has been found to result in cracks at bonding interfaces and sputtering layer,which degrades the bonding qualities.

关键词： wafer bonding induction heating MEMS MEMS packaging

Experimental study on high viscosity fluid micro-droplet jetting system

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science China(Technological sciences) 2010年第1期53卷 182-187页

作者： SHU XiaYun1,2,ZHANG HongHai1,2,LIU HuaYong1,2,XIE Dan1,2 & XIAO JunFeng1,2 1 School of mechanical science and engineering,Huazhong University of science and Technology,Wuhan 430074,China 2 Division of MOEMS,Wuhan National Laboratory of Optoelectronics,Wuhan 430074,China 1. School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of MOEMS Wuhan National Laboratory of Optoelectronics Wuhan 430074 China

Fluid dispensing is a method by which fluid materials(such as epoxy,adhesive,and encapsulant) are delivered in a controlled manner in electronics *** jetting,derived from inkjet technology,is a noncontact,data-driven fluid dispensing *** ideal fluid materials for packaging are usually high viscous,which is difficult to realize by traditional inkjet *** this paper,a mechanical micro-droplet jetting system for high viscosity fluid was *** consists of dispensing valve,motion stage,temperature control subsystem,pneumatic subsystem,driving circuit for solenoid valve,and system control *** of this system under various circumstances was studied by changing several parameters,including working temperature,stroke length,back pressure and drive pulse *** droplets of 0.35 mm in diameter were produced by stainless steel nozzle of 0.2 mm in diameter in the experimental study.

关键词： high viscosity fluid micro-jetting microelectronics packaging

Research for new method for high-precision non-contact measurement of rotate speed

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微计算机信息 2008年第4期 74-76页

作者： LIU YAN ZUO CHUNCHENG ZHANG YUMEI LI LIGANG(College of mechanical science and engineering, Jilin University,Changchun 130025) (ShanDong Institute of Business and Technology,YanTai 264005)

This paper explores a kind of new method of high-precision non-contact measurement of rotate speed, to acquire data with a laser CCD displacement sensor, and separate the low-frequency signal and high-frequency noise of the signal with the small-wave multi-frequency analysis method, to pick up the frequency for the separated low-frequency signal as the Nquist sampling theorem, to get the rotate speed to be measured. The experiment has proved this measurement method has the very good feasibility and effectiveness.

关键词： Laser CCD Non-contact measurement Multi-frequency analysis Rotate speed

UV-induced Self-initiated Graft Polymerization of Acrylamide onto Poly(ether ether ketone)

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Chemical Research in Chinese Universities 2012年第1期28卷 162-165页

作者： CHEN Rui-chao, SUN Hui, LI Ang and XU Guo-zhi College of Materials science and mechanical engineering, National Center for Quality Supervision and Test of Plastic Products, Beijing Technology and Business University, Beijing 100048, P. R. China Beijing Technol & Business Univ Coll Mat Sci & Mech Engn Natl Ctr Qual Supervis & Test Plast Prod Beijing 100048 Peoples R China

Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly（ether ether ketone）（PEEK） with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide（AAm） with ultraviolet（UV） irradiation in the presence or absence of benzophenone（BP）. The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy（SEM）, energy-disperse spectrometer（EDS） and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed.

关键词： Poly(ether ether ketone)(PEEK) UV-grafting Surface modification Self-initiation Graft polymerization

A Novel Approach to Solve the FMS Formation Problem

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Computer Aided Drafting,Design and Manufacturing 2001年第2期11卷 15-21页

作者： LiuZhong, ZhouYunfei, LiPeigen, Duan Zhengcheng School of mechanical science and engineering, Huazhong University of science and Technology, Wuhan 430074, China Manufacturing and Production School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China

We propose in this paper a genetic algorithm (GA)-based approach to solve the Flexible Manufacturing System (FMS) formation problem. First, we divide the unity of machines into small groups or cells using Group Technology (GT). And an option for considering the minimization of workload variation between cells is included. Then the implementation is done using GA. When using GA, the designer is allowed to specify the number of cells and impose lower and upper bounds on cell size. This makes the GA scheme flexible for solving the FMS formation problems.

关键词： group technology genetic algorithm FMS formation

A Generalized Acceleration and Deceleration Approach for Continuous Small Line Blocks with Look-ahead

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武汉理工大学学报 2006年第S3期28卷 1052-1058页

作者： LUO Fuyuan~1 ZHOU Yunfei~1 YIN Juan~2 (1.National Technical Research Center-Numerical Control System,School of mechanical science and engineering,Huazhang University of science and Technology,Wuhan 430074,China, 2.School of Machinery and Automobile engineering,Hefei University of Technology,Hefei 234009,China) National Technical Research Center-Numerical Control System School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Machinery and Automobile engineering Hefei University of TechnologyHefei 234009China

Generally complex 3D contours are divided into a lot of continuous small line blocks by CAD/CAM software. When these small line blocks are used in conventional way,machine tool has to stop at the end of one move before continuing on to the next to meet accuracy requirement,which results in ***-ahead is an intelligent function that aims at adjusting the feed rate automatically to achieve maximum productivity while maintaining *** now most researchers just utilize the simplest linear acceleration(ACC)and deceleration(DEC)to deal with look-ahead intelligence.A generalized ACC/DEC ap- proach and corresponding optimal look-ahead algorithm based on dynamic back tracking along a doubly linked list are *** improved rounding strategy for reducing interpolation errors is also *** using the proposed techniques,arbitrary velocity profiles that offer look-ahead feature and have the desired ACC/DEC characteristics for movement of a lot of continuous line blocks can be generated *** simulations and experiments showed the productivity was dramatically increased without sacri- fice of accuracy.

关键词： acceleration and deceleration numerical control back tracking look-ahead interpolation