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All-solid-state carbon-nanotube-fiber-based finger-muscle and robotic gripper

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International Journal of Smart and Nano Materials 2022年第1期13卷 64-78,I0004页

作者： Xia Liu Hua Ji Boyan Liu Qingsheng Yang institute of Modern Engineering Mechanics Department of Materials and ManufacturingBeijing University of TechnologyBeijingChina

Carbon nanotube fibers(CNTFs)have many desirable properties such as lightweight,high strength,high conductivity,and long *** CNTF is an ideal material for preparing electrochemically driven artificial *** previous studies focused mainly on the actuation performance of artificial muscles made of CNTF,this study focuses on an actuator that mimics human finger movements(flexion).More specifically,the preparation of CNTF muscles were optimized by twisting with ***,actuators are designed and assembled by combining all-solid-state CNTF muscles with polypropylene(PP)***,a dualelectrode system,which is infiltrated by a gel electrolyte,is built into the muscle *** addition,a robotic gripper is fabricated,which uses these *** study can help improve the design of CNTF-based muscle-actuators and future applications in robotics.

关键词： Carbon nanotube fibers artificial finger muscle twisted and coiled actuator electrochemical actuation module

A review on ductile mode cutting of brittle materials

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Frontiers of Mechanical Engineering 2018年第2期13卷 251-263页

作者： Elijah Kwabena ANTWI Kui LIU Hao WANG Department of Mechanical Engineering National University of Singapore Singapore Singapore institute of manufacturing Technology Singapore

Brittle materials have been widely employed for industrial applications due to their excellent mechanical, optical, physical and chemical properties. But obtaining smooth and damage-free surface on brittle materials by traditional machining methods like grinding, lapping and polishing is very costly and extremely time consuming. Ductile mode cutting is a very promising way to achieve high quality and crack-free surfaces of brittle materials. Thus the study of ductile mode cutting of brittle materials has been attracting more and more efforts. This paper provides an overview of ductile mode cutting of brittle materials including ductile nature and plasticity of brittle materials, cutting mechanism, cutting characteris- tics, molecular dynamic simulation, critical undeformed chip thickness, brittle-ductile transition, subsurface damage, as well as a detailed discussion of ductile mode cutting enhancement. It is believed that ductile mode cutting of brittle materials could be achieved when both crack-free and no subsurface damage are obtained simultaneously.

关键词： ductile mode cutting brittle materials critical undeformed chip thickness brittle-ductile transition subsurface damage molecular dynamic simulation

Finite element modeling of chip separation in machining cellular metals

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Advances in manufacturing 2015年第1期3卷 54-62页

作者： R.Guerra Silva U.Teicher A.Nestler A.Brosius School of Mechanical Engineering Central University of Venezuela institute of manufacturing Technology Dresden University of Technology

Cellular metals and metal foams belong to a young material group. Although it is desired to manufac- ture near-net-shape parts of cellular metals by primary shaping processes, additional secondary machining opera- tions are often unavoidable to obtain the required geome- tries and quality demands. Nevertheless, conventional machining of cellular metals leads to undesirable surface damage and poor precision. Furthermore, the chip forma- tion and the mechanism description of the surface damage are still unclear. A mesoscopic finite element model was developed to simulate the chip formation process in machining cellular metals. Experimental data of orthogonal machining tests were used to validate the finite element model. The cutting and thrust forces, as well as the images of the chip formation process of both experiments and simulations were compared and analysed. The model enabled the analysis of the chip formation and the surface defect mechanisms. The rake angle and cutting conditions affected the chip formation process, but the cell arrange- ment was detected as a decisive factor in the chip forma- tion and the resulting surface damage.

关键词： Cellular metals. Metal foams - MachiningFinite element modeling - Orthogonal cutting

A New Tolerance Allocation Approach Based on Fuzzy Comprehensive Evaluation and Annealing Evolution

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High Technology Letters 1999年第2期5卷 40-46页

作者：姬舒平 Advanced manufacturing Technology Center Harbin Institute of Technology Harbin 150001 China

A new approach of tolerance allocation is ***, manufacturing difficulties ζs of components of an assembly are evaluated using the Fuzzy Comprehensive evaluation, then a new mathematical model is established by combining their function sensitivity factor ωs, and finally, annealing evolution is used to solve the problem. The example shows that the approach can give tolerances more economically.

关键词： Tolerance allocation Fuzzy comprehensive evaluation (FCE) Annealing evolution(AE)

Experimental Study on Surface Integrity of Ti-6Al-4V in High Speed Side Milling

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Transactions of Tianjin University 2012年第3期18卷 206-212页

作者：杨晓勇任成祖王焱陈光 School of Mechanical Engineering Tianjin University Beijing Aeronautical manufacturing Technology institute

Aiming at the surface integrity of titanium alloy Ti-6Al-4V in high speed side milling, a series of side mill- ing tests were carried out with uncoated carbide milling cutter at various milling speeds. Surface roughness, residual stress, subsurface microstructure and microhardness variations were investigated. The surface roughness measurement results present that the milling speed from 80 to 120 m/min fails to produce better and more stable roughness values compared with the result obtained from 320 to 380 m/min. The residual stresses in the feed direction and axial depth of cut direction are in similar trends for the two milling speed levels mentioned above. Moreover, the residual stress pro- duced at 320 to 380 m/min is lower and more stable than that at 80 to 120 m/min. The microstructure analysis shows that the volume of β phase in the near surface becomes smaller and the deformation of β phase in the near surface be- comes obvious with the increase of the milling speed. Subsurface microhardness variation was observed down to 200 μm below the machined surface at 80 to 120 m/min and down to 160 μm at 320 to 380 m/min. It is concluded that better surface integrity and higher material removal rate can be obtained at 320 to 380 m/min than at 80 to 120 m/min.

关键词： surface roughness residual stress microhardness microstructure

Geometric Feature Extraction and Model Reconstruction Based on Scattered Data

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Journal of Donghua University(English Edition) 2004年第4期21卷 86-89页

作者：胡鑫习俊通金烨 institute of Computer Integrated manufacturing Shanghai Jiaotong University Shanghai 200030

A method of 3D model reconstruction based on scattered point data in reverse engineering is presented here. The topological relationship of scattered points was established firstly, then the data set was triangulated to reconstruct the mesh surface model. The curvatures of cloud data were calculated based on the mesh surface, and the point data were segmented by edge-based method; Every patch of data was fitted by quadric surface of freeform surface, and the type of quadric surface was decided by parameters automatically, at last the whole CAD model was created. An example of mouse model was employed to confirm the effect of the algorithm.

关键词： Reverse engineering Scattered data Feature extraction Model reconstruction.

Design and testing research of LiDAR for detecting atmospheric turbulence

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Optoelectronics Letters 2025年第3期21卷 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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A 16-bit sigma–delta modulator applied in micro-machined inertial sensors

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Journal of Semiconductors 2014年第4期35卷 128-133页

作者：徐宏林付强刘鸿娜尹亮王鹏飞刘晓为 MEMS Center Harbin Institute of Technology Key Laboratory of Micro-Systems and Micro-Structures manufacturing

A fourth-order low-distortion low-pass sigma-delta （∑△） modulator is presented for micro-machined inertial sensors. The proposed single-loop single-bit feedback modulator is optimized with a feed-forward path to decrease the nonlinearities and power consumption. The IC is implemented in a standard 0.6 μm CMOS technology and operates at a sampling frequency of 3.846 MHz. The chip area is 2.12 mm^2 with 23 pads. The experimental results indicate a signal-to-noise ratio （SNR） of 100 dB and dynamic range （DR） of 103 dB at an oversampling rate （OSR） of 128 with the input signal amplitude of-3.88 dBFS at 9.8 kHz; the power consumption is 15 raW at a 5 V supply.

关键词： analog-to-digital converter low-distortion low-pass sigma delta modulator micro-machined inertialsensor

Improved Methods for Process Routing in Enterprise Production Processes in Terms of Sustainable Development Ⅱ

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Tsinghua Science and Technology 2006年第6期11卷 693-700页

作者：谭显春刘飞刘大成郑力王海英张轶华 Department of Industrial Engineering Tsinghua University institute of manufacturing Engineering Chongqing University

The selection of process planning methods during production influences the enterprise＇s production process planning performance with determination of the process flow as the most important influencing factor. A new production process determining method that focuses on sustainable manufacturing was developed based on case-based reasoning, expert systems, and feature technology for designing the process flow of a new component. This study matches a new component with preview case process information, modifies the case process information if necessary, and selects the process flow for the new component based on a sustainable development assessment according to the similarities between the case and the sustainable development characteristics. The feasibility and practicability of the method is verified by a case study of a machining process flow design for a new component.

关键词： sustainable development process planning process routing diagnosis