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Optimization of Laser Ablation Technology for PDPhSM Matrix Nanocomposite Thin Film by Artificial Neural Networks-particle Swarm Algorithm

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 188-193页

作者：唐普洪宋仁国 The moe key laboratory of mechanical manufacture and automation Zhejiang University of Technology Jiaxing Vocational Technical College

A new thermal ring-opening polymerization technique for 1, 1, 3, 3-tetra-ph enyl-1, 3-disilacyclobutane （TPDC） based on the use of metal nanoparticles produced by pulsed laser ablation was investigated. This method facilitates the synthesis of polydiphenysilylenemethyle （PDPhSM） thin film, which is difficult to make by conventional methods because of its insolubility and high melting point. TPDC was first evaporated on silicon substrates and then exposed to metal nanoparticles deposition by pulsed laser ablation prior to heat *** TPDC films with metal nanoparticles were heated in an electric furnace in air atmosphere to induce ring-opening polymerization of TPDC. The film thicknesses before and after polymerization were measured by a stylus profilometer. Since the polymerization process competes with re-evaporation of TPDC during the heating, the thickness ratio of the polymer to the monomer was defined as the polymerization efficiency, which depends greatly on the technology conditions. Therefore, a well trained radial base function neural network model was constructed to approach the complex nonlinear relationship. Moreover, a particle swarm algorithm was firstly introduced to search for an optimum technology directly from RBF neural network model. This ensures that the fabrication of thin film with appropriate properties using pulsed laser ablation requires no in-depth understanding of the entire behavior of the technology conditions.

关键词： nanocomposite thin film pulsed laser deposition(PLD) artificial neural net- works(ANN) particle swarm optimization (PSO)

Overview of research on agricultural robots in China

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International Journal of Agricultural and Biological Engineering 2008年第1期1卷 12-21页

作者： Zhang Libin Yang Qinghua Bao Guanjun Wang Yan Qi Liyong Gao Feng Xu Fang The moe key laboratory of mechanical manufacture and automation Zhejiang University of TechnologyHangzhou 310012China

As the representation of new concept agricultural machinery,agricultural robots possess great advantages of improving agricultural productivity,enhancing production environment and solving the problem of labor ***,the strategy for application of agricultural robots and precision agriculture to improve the intelligence and information level of agriculture is the inevitable trend for China’s agriculture in the twentieth *** on the developmental status of agricultural robots in China,the agricultural robots are categorized and the performances,structures and characteristics of various agricultural robots such as vegetable grafting robots,transplanting robots,spraying robots,mowing robots,harvesting robots,grading and detecting robots are amply *** can be seen that vegetable grafting robots,spraying robots,harvesting robots,grading and detecting robots have already been put into production while others are still at experimental *** present,there are several problems such as low popularization,great limitations,high cost and low intelligence,which greatly restrict the development of agricultural robots in ***,open agricultural robot system with good expansibility,generality and flexibility should be developed and adopted to decrease its cost and shorten developing *** mechanical structure of robots should also be designed as simply as ***,multi-robot system would become another important development direction of agricultural robots in the future.

关键词： agriculturalrobots robotsforfacilitybreeding robotsforfieldmanagement robots forharvesting robots for gradingand detecting

Structure and erosion resistance of Ni60A/SiC coatting by laser cladding

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维普期刊数据库

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中国有色金属学会会刊：英文版 2006年第3期16卷 643-646页

作者：楼白杨陈阵白万金董刚 moe key laboratory of mechanical manufacture and automation Institute of Material and Surface Engineering Zhejiang University of Technolo gy Hangzhou 310014 China

The Ni60A and Ni60A/SiC coatings were obtained by laser cladding on 0.45% C steel. The microstructure and hardness of the coatings were studied by SEM and XRD. The erosion resistances of Ni60A and Ni60A/SiC coatings were also investigated. The results show that the structure of different coatings is up to the temperature gradient and solidifying velocity in metal-melting region during laser cladding process. The coatings consist of a cladding layer, in which dendritic crystal and bulky cell-like crystal exist mainly, and a thermo-affected layer. Ni60A/SiC coating has higher microhardness than that of Ni60A coating, which is mainly caused by SiC and complicated phases formed by Ni, Cr, Fe, C and Si. It is obvious from the erosion test that the Ni60A/SiC coating has high erosion resistance.

关键词：激光熔覆 Ni60A SiC 抗腐蚀性结构涂层

Effects of oxygen pressure on La_3Ga_5SiO_(14) thin films grown by pulsed laser deposition

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Journal of Rare Earths 2010年第3期28卷 420-423页

作者：张雯王继扬季振国李红霞娄垚姚淑华 State key laboratory of Crystal Materials Shandong University Institute of Electronic Information Hangzhou Dianzi University The moe key laboratory of the mechanical manufacture and automation Zhejiang University of Technology

La3Ga5SiO14 thin films were grown on Si(100) substrates by pulsed laser deposition at several oxygen pressures(5,10,and 20 Pa).The effects of oxygen pressure on the structural and morphological characteristics of the films were investigated using X-ray diffraction,atomic force microscopy,and scanning electron microscopy.X-ray diffraction results showed the intensity of lines from crystallites oriented along the(300) and(220) planes increased as the oxygen pressure was increased to 20 *** deposited films ...

关键词： thin films pulsed laser deposition crystal structure surfaces rare earths

Tool wear criterion,tool life,and surface roughness during high-speed end milling Ti-6Al-4V alloy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 587-595页

作者： Song ZHANG Jian-feng LI moe Key Laboratory of High Efficiency and Clean Mechanical Manufacture School of Mechanical Engineering Shandong University Jinan 250061 China

The objective of the present research is to investigate the relationship among tool wear, surface topography, and surface roughness when high-speed end milling Ti-6Al-4V alloy, and also to define an optimal flank wear criterion for the cutting tool to integrate tool life and the surface roughness requirements of the finish milling process. An annealed Ti-6Al-4V alloy was selected as the workpiece material, undergoing end milling with uncoated carbide inserts. The flank wear of the insert was observed and measured with the toolmaker's microscope. To examine machined surfaces, 3D surface topography was provided by the white light interferometer, and the arithmetical mean roughness (Ra) was calculated with the WYKO Vision32 software. The flank wear increases with cutting time, and the maximal flank wear is set as the flank wear criterion. As the cutting process progresses, tool wear is the predominant factor affecting the variation of surface roughness. According to the plots for the tool wear propagation and surface roughness variation, an optimal flank wear criterion can be defined which integrates the tool life and the surface roughness requirements for the finish milling process.

关键词： Tool wear Surface topography Surface roughness Optimal flank wear criterion

Preparation of Electrode Array by Electrochemical Etching Based on FEM

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Journal of Materials Science & Technology 2008年第6期24卷 845-849页

作者： Minghuan WANG Di ZHU Lei WANG The moe key laboratory of mechanical manufacture and automation Zhejiang University of Technology Hangzhou 310032 China College of mechanical and Electrical Engineering Nanjing Aeronautics and Astronautics Nanjing 210016 China

Process technology of multiple cylindrical micro-pins by wire-electrical discharge machining （wire-EDM） and electrochemical etching was presented. A row of rectangular micro-columns were machined by wire-EDM and then machined into cylindrical shape by electrochemical etching. However, the shape of the multiple electrodes and the consistent sizes of the electrodes row are not easy to be controlled. In the electrochemical process, the shape of the cathode electrode determines the current density distribution on the anode and so the forming of multiple electrodes. This paper proposes a finite element method （FEM） to accurately optimize the electrode profile. The microelectrodes row with uniformity diameters with size from hundreds micrometers to several decades could be fabricated, and mathematical model controlling the shape and diameter of multiple microelectrodes was provided. Furthermore, a good agreement between experimental and theoretical results was confirmed.

关键词： Electrode array Electrochemical etching Finite element method (FEM) Micro-electrodes

Separate Control of High Frequency Electro-hydraulic Vibration Exciter

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Chinese Journal of mechanical Engineering 2011年第2期24卷 293-302页

作者： JIA Wen＇ang RUAN Jian REN Yan The key laboratory of mechanical manufacture and automation of Ministry of Education Zhejiang University of Technology Hangzhou 310032 China

The working frequency of the conventional electro-hydraulic vibration exciters,which consist of a servo valve and a hydraulic cylinder,is generally restricted within a narrow range due to limited frequency response capability of the servo valve *** counteract such restriction,a novel scheme for an electro-hydraulic vibrator,controlled by a two-dimensional valve（2D valve） and a bias valve in parallel,is therefore *** frequency,amplitude and offset are independently controlled by rotary speed,axial sliding of the spool of the 2D valve and axial sliding of the spool of the bias *** principle of separate control was presented and the regulation approach of frequency,amplitude and offset was discussed.A mathematical model of the hydraulic power mechanism for the proposed vibration exciter was established to investigate the relationship between the amplitude and the axial sliding of the 2D valve＇ spool,as well as that between the offset and the axial sliding of the bias valve＇s spool at various *** experimental system was built to validate the theoretical *** is verified that the 2D exciter is capable of working smoothly in a frequency range of 5- 200 *** its frequency,amplitude and offset can be controlled respectively by either closed loop or open loop *** is a linear relationship between the output amplitude and the spool axial opening of the 2D valve until a point when the flow rate becomes saturate and the amplitude remains *** offset displacement of the cylinder＇s piston is linearly proportional to the axial displacement of the spool of the bias valve,when the valve opening is less than 25%.Thereafter,the slop of the offset curve decreases and tends to *** proposed electro-hydraulic vibration controlled by the 2D valve not only facilitates the realization of high-frequency electro-hydraulic vibration,the high-accuracy of vibration can also be achieved by means of independent controls to the freque

关键词： control valves electro-hydraulic system vibration exciter dynamics characteristics

Adaptive Change Detection for Long-Term Machinery Monitoring Using Incremental Sliding-Window

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Chinese Journal of mechanical Engineering 2017年第6期30卷 1338-1346页

作者： Teng Wang Guo-Liang Lu Jie Liu Peng Yan key laboratory of High-Efficiency and Clean mechanical manufacture of moe School of Mechanical EngineeringShandong University Department of mechanical and Aerospace Engineering Carleton University

Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detection delay that limits their usages in real applications. This paper presents a new adaptive real-time change detection algorithm, an extension of the recent research by combin- ing with an incremental sliding-window strategy, to handle the multi-change detection in long-term monitoring of machine operations. In particular, in the framework, Hil- bert space embedding of distribution is used to map the original data into the Re-producing Kernel Hilbert Space （RK_HS） for change detection; then, a new adaptive threshold strategy can be developed when making change decision, in which a global factor （used to control the coarse-to-fine level of detection） is introduced to replace the fixed value of threshold. Through experiments on a range of real testing data which was collected from an experimental rotating machinery system, the excellent detection performances of the algorithm for engineering applications were demonstrated. Compared with state-of- the-art methods, the proposed algorithm can be more suitable for long-term machinery condition monitoring without any manual re-calibration, thus is promising in modern industries.

关键词： Machine monitoring Change detection Long-term monitoring Adaptive threshold

Kinematics and trajectory planning of a cucumber harvesting robot manipulator

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International Journal of Agricultural and Biological Engineering 2009年第1期2卷 1-7页

作者： Zhang Libin Wang Yan Yang Qinghua Bao Guanjun Gao Feng Xun Yi The moe key laboratory of mechanical manufacture and automation Zhejiang University of TechnologyHangzhou 310012China

In order to reduce cucumber harvesting cost and improve economic benefits,a cucumber harvesting robot was *** cucumber harvesting robot consists of a vehicle,a 4-DOF articulated manipulator,an end-effector,an upper monitor,a vision system and four DC servo drive *** Kinematics of the cucumber harvesting robot manipulator was constructed using D-H coordinate frame *** the inverse kinematics which provides a foundation for trajectory planning has been solved with inverse transform *** cycloidal motion,which has properties of continuity and zero velocity and acceleration at the ports of the bounded interval,was adopted as a feasible approach to plan trajectory in joint space of the cucumber harvesting robot ***,hardware and software based on CAN-bus communication between the upper monitor and the joint controllers have been *** results show that the upper monitor communicates with the four joint controllers efficiently by CAN-bus,and the integrated errors of four joint angles do not exceed four *** factors resulting in the errors were analyzed and the corresponding solutions for improving precision are proposed.

关键词： cucumber harvesting robot articulated manipulator trajectory planning cycloidal motion CAN-bus