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Frontiers of Mechanical Engineering 2019年第3期14卷 255-272页

作者： Chengyuan LIANG Fang YUAN Xuedong CHEN Wei JIANG Lizhan ZENG Xin LUO State key laboratory of Digital manufacturing Equipment and technology Huazhong University of Science and Technology Wuhan 430074 China

Nano-precision positioning stages are characterized by rigid-flexible coupling systems. The complex dynamic characteristics of mechanical structure of a stage, which are determined by structural and dynamic parameters, exert a serious influence on the accuracy of its motion and measurement. Systematic evaluation of such influence is essential for the design and improvement of stages. A systematic approach to modeling the dynamic accuracy of a nano-precision positioning stage is developed in this work by integrating a multi-rigid-body dynamic model of the mechanical system and measurement system models. The influence of structural and dynamic parameters, including aerostatic bearing configurations, motion plane errors, foundation vibrations, and positions of the acting points of driving forces, on dynamic accuracy is investigated by adopting the H-type configured stage as an example. The approach is programmed and integrated into a software framework that supports the dynamic design of nano-precision positioning stages. The software framework is then applied to the design of a nano-precision positioning stage used in a packaging lithography machine.

关键词： nano-precision positioning stage analysis and design structural and dynamic parameters dynamic accuracy systematic modeling

Flexible sensors with zero Poisson's ratio

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National Science Review 2024年第5期11卷 153-169页

作者： Xin Huang Tianzhao Bu Qingyang Zheng Shaoyu Liu Yangyang Li Han Fang Yuqi Qiu Bin Xie Zhouping Yin Hao Wu Department of Mechanical Engineering Flexible Electronics Research Center State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and Technology Department of Electronic Science and technology School of Integrated CircuitsHuazhong University of Science and Technology

Flexible sensors have been developed for the perception of various stimuli. However, complex deformation,usually resulting from forces or strains from multi-axes, can be challenging to measure due to the lack of independent perception of multiaxial stimuli. Herein, flexible sensors based on the metamaterial membrane with zero Poisson's ratio(ZPR) are proposed to achieve independent detection of biaxial stimuli. By deliberately designing the geometric dimensions and arrangement parameters of elements, the Poisson's ratio of an elastomer membrane can be modulated from negative to positive, and the ZPR membrane can maintain a constant transverse dimension under longitudinal stimuli. Due to the accurate monitoring of grasping force by ZPR sensors that are insensitive to curvatures of contact surfaces, rigid robotic manipulators can be guided to safely grasp deformable objects. Meanwhile, the ZPR sensor can also precisely distinguish different states of manipulators. When ZPR sensors are attached to a thermal-actuation soft robot, they can accurately detect the moving distance and direction. This work presents a new strategy for independent biaxial stimuli perception through the design of mechanical metamaterials, and may inspire the future development of advanced flexible sensors for healthcare, human–machine interfaces and robotic tactile sensing.

关键词： zero Poisson's ratio metamaterials independent perception of multiaxial stimuli flexible sensor

High precision and efficiency robotic milling of complex parts:Challenges,approaches and trends

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Chinese Journal of Aeronautics 2022年第2期35卷 22-46页

作者： Zerun ZHU Xiaowei TANG Chen CHEN Fangyu PENG Rong YAN Lin ZHOU Zepeng LI Jiawei WU School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State key laboratory of Digital manufacturing Equipment and technology Huazhong University of Science and TechnologyWuhan 430074China Wuhan Digital design and manufacturing Innovation Centre Co. Ltd.Wuhan 430074China

Due to the advantages of large workspace,low cost and the integrated vision/force sensing,robotic milling has become an important way for machining of complex *** recent years,many scholars have studied the problems existing in the applications of robotic milling,and lots of results have been made in the dynamics,pose planning,deformation control etc.,which provides theoretical guidance for high precision and high efficiency of robotic *** the perspective of complex parts robotic milling,this paper focuses on machining process planning and control techniques including the analysis of the robot-workspace,robot trajectory planning,vibration monitoring and control,deformation monitoring and *** well as the principles of these technologies such as robot stiffness characteristics,dynamic characteristics,chatter mechanisms,and deformation *** methods and characteristics related to the theory and technology of robotic milling of complex parts are summarized *** latest research progress and achievements in the relevant fields are *** is hoped that the challenges,strategies and development related to robotic milling could be clarified through the carding work in this paper,so as to promote the application of related theories and technologies in high efficiency and precision intelligent milling with robot for complex parts.

关键词： Complex parts Deformation Dynamics Robotic milling Stiffness Vibration control

Rules Mining-Based Gene Expression Programming for the Multi-Skill Resource Constrained Project Scheduling Problem

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2815-2840页

作者： Min Hu Zhimin Chen Yuan Xia Liping Zhang Qiuhua Tang key laboratory of Metallurgical Equipment and Control technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081China Hubei key laboratory of Mechanical Transmission and manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China Precision manufacturing Institute Wuhan University of Science and TechnologyWuhan430081China China Ship Development and design Center Wuhan430060China

Themulti-skill resource-constrained project scheduling problem(MS-RCPSP)is a significantmanagement science problem that extends from the resource-constrained project scheduling problem(RCPSP)and is integrated with a real project and production *** solve MS-RCPSP,it is an efficient method to use dispatching rules combined with a parallel scheduling mechanism to generate a scheduling *** paper proposes an improved gene expression programming(IGEP)approach to explore newly dispatching rules that can broadly solve MS-RCPSP.A new backward traversal decoding mechanism,and several neighborhood operators are applied in *** backward traversal decoding mechanism dramatically reduces the space complexity in the decoding process,and improves the algorithm’s *** neighborhood operators improve the exploration of the potential search *** experiment takes the intelligent multi-objective project scheduling environment(iMOPSE)benchmark dataset as the training set and testing set of *** newly dispatching rules are discovered and extracted by IGEP,and eight out of ten are superior to other typical dispatching rules.

关键词： Project scheduling multi-skill gene expression programming dispatching rules

Novel Cylinder Movement Modeling Method Based on Aerodynamics

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1193-1202页

作者： Jian-Qing Zhang Xiao-Mei Hu Jin-Sheng Kang Feng Xiong Ning Zeng School of Mechatronic Engineering and Automation Key Laboratory of Intelligent Manufacturing and RoboticsShanghai University College of Engineering Design and Physical SciencesBrunel University London

The cylinder movement is affected by multiple factors and it is difficult to establish the accurate movement model of the cylinder. In order to improve the reliability of the production line design and to speed up the production line debugging, a novel cylinder movement modeling method based on aerodynamics is proposed. The kinetic theory, thermodynamic theory and kinematics knowledge are applied and integrated various factors which affect the movement characteristics of the cylinder are considered. According to the proposed mathematical model of cylinder movement, thecombined simulation software of cylinder movement based on Visual Studio and Visual Component （3D Create） is developed to calculate thevelocity, accel- eration and movement time of the cylinders during the running of the assembly line. Comparison results of cylinder＇s movement time under different intake air and displacement show that the mathematical model of cylinder movement based on aerodynamic is more accurate and the degree of fittingis 0.9846, which proves the effectiveness of the combined simulation software of cylinder movement. By the cylinder movement modeling method based on aerodynamic, accurate value of takt and the debug parameters can be calculated as a reference for the designers and debuggers of the cylinder-driven assembly lines.

关键词： Aerodynamics Thermodynamics Cylindercharacteristic Combined simulation

design and testing research of LiDAR for detecting atmospheric turbulence

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Optoelectronics Letters 2025年第3期 172-176页

作者： QIU Duoyang LI Xianyang YANG Hao ZHU Xiaomeng FANG Zhiyuan XU Xiang School of Advanced manufacturing Engineering Hefei University Anhui Provincial Engineering technology Research Center of Intelligent Vehicle Control and integrated design technology Hefei University Science Island Branch of Graduate School University of Science and Technology of China School of Mechanical and Energy Engineering Ningbo Tech University key laboratory of Atmospheric Optics Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences

Atmospheric turbulence is an important parameter affecting laser atmospheric transmission. This paper reports on a self-developed atmospheric turbulence detection Li DAR system (scanning differential image motion Li DAR(DIM-Li DAR) system). By designing and simulating the optical system of atmospheric turbulence detection Li DAR,the basic optical imaging accuracy has been determined.

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Raster to Vector Conversion for Engineering Drawings:Survey and Prospect

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Computer Aided Drafting,design and manufacturing 2006年第2期16卷 71-77页

作者： CHENG Bin ZHANG Shu-sheng SHI Yun-fei LEI Guang-ming The key laboratory of contemporary design and integrated manufacturing technology Ministry of Education Northwestern Polytechnical University Xi＇an 710072 China School of Science Xi＇an University of Architecture ＆ Technology Xi＇an 710055 China

Recent development and recognition methods of raster to vector conversion for engineering drawings are presented. The advantages and disadvantages of all existing models are analyzed. Some research challenges and futu... 详细信息

关键词： raster to vector conversion graphic recognition engineering drawings vectorization

Build orientation determination of multi-feature mechanical parts in selective laser melting via multi-objective decision making

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Frontiers of Mechanical Engineering 2023年第2期18卷 227-251页

作者： Hongsheng SHENG Jinghua XU Shuyou ZHANG Jianrong TAN Kang WANG Engineering Research Center for design Engineering and Digital Twin of Zhejiang Province Zhejiang UniversityHangzhou 310027China State key laboratory of Fluid Power and Mechatronic Systems Hangzhou 310027China key laboratory of Advanced manufacturing technology of Zhejiang Province Hangzhou 310027China

Selective laser melting(SLM)is a unique additive manufacturing(AM)category that can be used to manufacture mechanical *** has been widely used in aerospace and automotive using metal or alloy *** build orientation is crucial in AM because it affects the as-built part,including its part accuracy,surface roughness,support structure,and build time and cost.A mechanical part is usually composed of multiple surface *** surface features carry the production and design knowledge,which can be utilized in SLM *** study proposes a method to determine the build orientation of multi-feature mechanical parts(MFMPs)in ***,the surface features of an MFMP are recognized and grouped for formulating the particular optimization ***,the estimation models of involved optimization objectives are established,and a set of alternative build orientations(ABOs)is further obtained by many-objective ***,a multi-objective decision making method integrated by the technique for order of preference by similarity to the ideal solution and cosine similarity measure is presented to select an optimal build orientation from those *** weights of the feature groups and considered objectives are achieved by a fuzzy analytical hierarchy *** case studies are reported to validate the proposed method with numerical results,and the effectiveness comparison is *** manufacturing is conducted to prove the performance of the proposed *** measured average sampling surface roughness of the most crucial feature of the bracket in the original orientation and the orientations obtained by the weighted sum model and the proposed method are 15.82,10.84,and 10.62μm,*** numerical and physical validation results demonstrate that the proposed method is desirable to determine the build orientations of MFMPs with competitive results in SLM.

关键词： selective laser melting(SLM) build orientation determination multi-feature mechanical part(MFMP) fuzzy analytical hierarchy process multi-objective decision making(MODM)

Automated Dimensioning Method of Engineering Drawings for Mechanical Products Based on Curve Chain

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Computers, Materials & Continua 2020年第10期65卷 847-863页

作者： Gui Li Peng Yang key laboratory of Metallurgical Equipment and Control technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081China Hubei key laboratory of Mechanical Transmission and manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China

An automated method based on the curve chain was proposed for dimensioning of engineering drawings for the mechanical *** to the internal relation between the features of 3D model feature and elements of 2D drawing,the curve chain was established to reflect the geometric topological structure between the *** divides the dimensions into the absolute dimensions within the cure chain and the relative dimensions between the curve *** parallel and lengthy relationship between the drawing elements of the constructed X and Y parallel matrix was solved to remove redundant elements in the curve chain and labeled the absolute dimensions of the remaining valid *** average minimum weight coefficient was introduced to judge the dependence on the relative dimensions between curve *** the analysis of the overlap between the circular rectangular areas,including all the absolute dimensions of the curve chains,overlapping curve chains were merged,and their dimensions were rearranged to avoid the cross interference between *** method was seamlessly integrated into the drafting module of product design software NX,and it developed an automated dimensioning *** examples show that the system has excellent interactivity and robustness in the dimensioning of product engineering *** dimension information is complete,accurate and reliable.

关键词： Automated dimensioning engineering drawing curve chain mechanical product weight coefficient

The Effects of the Geometry of a Current Collector with an Equal Open Ratio on Output Power of a Direct Methanol Fuel Cell

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Energy Engineering 2024年第5期121卷 1161-1172页

作者： Yingli Zhu Jiachi Xie Mingwei Zhu Jun Zhang Miaomiao Li Tianjin key laboratory of integrated design and On-line Monitoring for Light Industry&Food Machinery and Equipment School of Mechanical EngineeringTianjin University of Science&TechnologyTianjin300222China Tianjin College University of Science and Technology BeijingTianjin301830China Jiangsu key laboratory of Precision and Micro-manufacturing technology College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China

The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)*** a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too little attention has been given to how geometry(including the shape and feature size of the flow field)affects a current collector with an equal open *** this paper,perforated and parallel current collectors with an equal open ratio of 50%and different feature sizes are designed,and the corresponding experimental results are shown to explain the geometry effects on the output power of the *** results indicate that the optimal feature sizes are between 2 and 2.5 mm for both perforated and parallel flow field in the current collectors with an equal open ratio of 50%.This means that for passive methanol fuel cells,to achieve the highest output power,the optimal feature size of the flow field in both anode and cathode current collectors is between 2 and 2.5 mm under the operating mode of this *** effects of rib and channel position are also investigated,and the results indicate that the optimum pattern depends on the feature sizes of the flow field.

关键词： Direct methanol fuel cell geometry open ratio current collector position