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A New Method for Type Synthesis of 2R1T and 2T1R 3-DOF Redundant Actuated Parallel Mechanisms with Closed Loop Units

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 134-157页

作者： Yongquan Li Yang Zhang Lijie Zhang Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao066004China Key Laboratory of Advanced Forging&Stamping Technology and Science Ministry of Education of ChinaYanshan UniversityQinhuangdao066004China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen518052China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityQinhuangdao066004China

The current type synthesis of the redundant actuated parallel mechanisms is adding active-actuated kinematic branches on the basis of the traditional parallel mechanisms,or using screw theory to perform multiple getting intersection and union to complete type *** number of redundant parallel mechanisms obtained by these two methods is *** this paper,based on Grassmann line geometry and Atlas method,a novel and effective method for type synthesis of redundant actuated parallel mechanisms(PMs)with closed-loop units is ***,the degree of freedom(DOF)and constraint line graph of the moving platform are determined successively,and redundant lines are added in constraint line graph to obtain the redundant constraint line graph and their equivalent line graph,and a branch constraint allocation scheme is formulated based on the allocation ***,a scheme is selected and redundant lines are added in the branch chains DOF graph to construct the redundant actuated branch chains with closed-loop ***,the branch chains that meet the requirements of branch chains configuration criteria and F&C(degree of freedom&constraint)line graph are *** this paper,two types of 2 rotational and 1 translational(2R1T)redundant actuated parallel mechanisms and one type of 2 translational and 1 rotational(2T1R)redundant actuated parallel mechanisms with few branches and closed-loop units were taken as examples,and 238,92 and 15 new configurations were *** the mechanisms contain closed-loop units,and the mechanisms and the actuators both have good ***,all the mechanisms have excellent comprehensive performance,in which the two rotational DOFs of the moving platform of 2R1T redundant actuated parallel mechanism can be independently *** instantaneous analysis shows that all mechanisms are not instantaneous,which proves the feasibility and practicability of the method.

关键词： Redundant actuated Parallel mechanisms Type synthesis Atlas method Instantaneous analysis

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δ-phase precipitation regularity of cold-rolled fine-grained GH4169 alloy plate and its effect on mechanical properties

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Transactions of Nonferrous Metals Society of China 2020年第12期30卷 3287-3295页

作者： Hao XUE Jing-qi ZHAO Yong-kang LIU Chun-xiang ZHANG Jun-ting LUO Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Cold rolling and heat-treatment were used for the grain refinement of GH4169 superalloy *** effects of cold rolling reduction ratio and heat-treatment time on the precipitatedδphase,and the effects ofδ-phase content and morphology on the mechanical properties of the GH4169 alloy plates,are *** results demonstrate that coldrolling can promote the precipitation of theδphase and its transformation from theδ-Ni3Nb phase to theδ-NbNi4 *** comprehensive properties of the alloy are better when the heat treatment time is 1 h,with 132 MPa increase in the tensile strength and only 2.9%decrease in the elongation relative to those of the original *** mechanical properties of the alloy are shown to change greatly with the change in theδ-phase morphology.

关键词： fine-grained GH4169 alloy cold rolling δphase mechanical properties

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Principle of Multi-roller Straightening Process and Quantitative Resolutions of Straightening Strategies

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Journal of Iron and Steel Research International 2014年第9期21卷 823-829页

作者： Jing YIN Jun ZHAO Shi-yan WANG Xian-song WAN Yue-lin LI College of Mechanical Engineering Ningbo University of Technology Key Laboratory of Advanced Forging and Stamping Technology and Science(Yanshan University) Ministry of Education of China CISDI R&D Co. Ltd.

The multi-roller straightening process of section steel is analyzed by the springback theory of small curva- ture plane bending. The theoretical analysis results prove the curvature unification in straightening process and clear- ly reveal the principle of the multi-roller straightening process. The principle can be described as~ the initial curva- tures are reduced by several times anti-bendingl meanwhile the initial curvature differences are diminished and the residual curvatures are unified~ finally, the member after curvature unification is straightened by the last anti-ben- ding. With the plastic region ratios becoming larger, the initial curvatures are more easily unified in straightening process. Based on the plastic region ratios and the required number of roller systems for unifying the initial curva- tures, the large deformation straightening strategy and the small deformation straightening strategy are redefined. The new definition provides an important theoretical basis for setting reliable reduction rules. Through the theoretical analysis results, a new straightener design philosophy is proposed to improve the straightening quality and further increase the adjustment precision as well as the flexibility of the last roller system. The adjustable end roller emerges as the times required, achieving a good effect in practical application.

关键词： section steel multi-roller straightening curvature unification plastic region ratio straightening strategy

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Kinematic,Workspace and Force Analysis of A Five-DOF Hybrid Manipulator R(2RPR)R/SP+RR

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 232-243页

作者： Yundou Xu Fan Yang Youen Mei Dongsheng Zhang Yulin Zhou Yongsheng Zhao Laboratory of Parallel Robot and Mechatronic System of Hebei Province Yanshan UniversityQinhuangdao 066004China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of National Education Yanshan UniversityQinhuangdao 006004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Tencent Robotics X Tencent HoldingsShenzhen 518057China

In the present study,the over-constrained hybrid manipulator R(2RPR)R/SP+RR is considered as the research *** this paper,kinematics of the hybrid manipulator,including the forward and inverse position,are ***,the workspace is checked based on the inverse position solution to evaluate whether the workspace of the hybrid manipulator meets the requirements,and the actual workspace of the hybrid robot is *** that,the force analysis of the over-constrained parallel mechanism is carried out,and an ADAMS-ANSYS rigid-flexible hybrid body model is established to verify the *** on the obtained results from the force analysis,the manipulator structure is ***,the structure optimization is carried out to improve the robot ***,calibration and workspace verification experiments are performed on the prototype,cutting experiment of an S-shaped aluminum alloy workpiece is completed,and the experiment verifies the machining ability of the *** work conducts kinematics,workspace,force analyses,structural optimization design and experiments on the over-constrained hybrid manipulator R(2RPR)R/SP+RR,providing design basis and technical support for the development of the novel hybrid manipulator in practical engineering.

关键词： Hybrid manipulator Over-constrained Kinematic analysis Stiffness analysis

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Differential evolution based quantum genetic algorithm and its application

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Journal of Computational Information Systems 2014年第1期10卷 1-8页

作者： Jiang, Wanlu Zhang, Sheng Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Key Laboratory of Advanced Forging and Stamping Technology and Science Ministry of Edu. of China Yanshan University Qinhuangdao 066004 China

In the traditional quantum genetic algorithm, the rotation angle and direction of the quantum rotation gate should be looked up from the lookup table which has been designed according to the specific problem. However, this way to solve optimization problems has strong pertinence and poor efficiency so as to miss the global optimal value. For overcome this drawback, the rotation angle and the direction of the quantum rotation gate is determined with the differential evolution algorithm instead, which is a high-efficiency and adaptable evolutionary algorithm. The improved algorithm is applied to solve the function optimization problem, and the numerical results indicate that the improved algorithm has more efficiency and the stronger global optimal capacity. The improved algorithm can be used to optimize the rolling schedule of the tandem cold rolling mills, and the experiment demonstrates that the quantum genetic algorithm based on the differential evolution algorithm is an effective and feasible intelligence method for rolling schedule optimization. Copyright © 2014 Binary Information Press.

关键词： Table lookup

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抛物线型零件固体颗粒介质成形变形理论研究(英文)

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2017年第3期18卷 194-211页

作者： Xiang-dong JIA Chang-cai ZHAO Jian-chao LI Liu-yang HE MOE Key Laboratory of Advanced Forging & Stamping Technology and Science Yanshan University Qinhuangdao 066004 China

目的:板材固体颗粒介质成形工艺作为一种新型的软模成形技术,是采用固体颗粒代替刚性凸模或凹模(或弹性体、液体)对板料进行成形加工的工艺。固体颗粒介质板材拉深成形工艺为拉深和胀形两种变形模式的复合成形,其变形过程与传统拉深成... 详细信息

目的:板材固体颗粒介质成形工艺作为一种新型的软模成形技术,是采用固体颗粒代替刚性凸模或凹模(或弹性体、液体)对板料进行成形加工的工艺。固体颗粒介质板材拉深成形工艺为拉深和胀形两种变形模式的复合成形,其变形过程与传统拉深成形工艺有很大的区别。以抛物线型零件为研究对象,对其成形过程进行研究,建立固体颗粒介质板材软凸模拉深成形的几何条件和应变计算公式。创新点:1.首次提出了描述固体颗粒介质板材拉深成形变形机理的拉深权和胀形权的概念,并建立了相应的计算公式;2.建立了固体颗粒介质抛物线型零件软凸模拉深成形的几何条件和应变计算公式。方法:1.通过对抛物线型零件固体颗粒介质拉深成形的变形过程分析(图1~3),将变形过程和成形工件的变形区进行划分;2.将数学中权函数的思想引入到对抛物线型零件固体颗粒介质拉深成形的分析中,提出拉深权和胀形权的定义及相应表达式(公式(1)和(2));3.通过理论推导,构建不同成形阶段抛物线型零件拉深成形过程中的应变计算式(公式(28)^(30)和公式(62a)^(62c))和壁厚计算公式(公式(31)和(63));4.利用MATLAB编制抛物线型零件拉深成形应变计算程序(图14);5.以某航空零件为目标零件,通过试验试制不同成形条件下不同阶段的抛物线型工件(表2和3),将理论计算壁厚与实测厚度进行对比(图19),将试验轮廓与理论计算轮廓进行对比(图21),验证分析过程中所提假设及理论计算的可行性和正确性;将试验获得成形工件的几何尺寸(表3)代入MATLAB计算程序中,对该航空零件的变形过程进行分析(图15、18、19、21和22)。结论:1.固体颗粒介质拉深成形过程是胀形和拉深的复合成形,通过对其变形过程分析,首次提出了拉深权和胀形权的概念,并且给出了其计算公式。成形过程中,拉深权越大,工件成形后的壁厚差越小;胀形权则正好相反。2.利用拉深权和胀形权,建立了固体颗粒介质软凸模拉深成形变形区应变计算公式,且可以计算出应变分界圆位置半径,为分析固体颗粒介质软凸模拉深成形工艺变形过程提供了新的理论依据。3.设置合理的成形条件、拉深权的提高和应变分界圆半径的缩小可以降低拉深成形过程中底部的过度减薄,进而提高极限成形高度。

关键词：固体颗粒介质软模成形拉深拉深权胀形权应变

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Research of refrigeration system for a new type of constant temperature hydraulic tank

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High technology Letters 2016年第4期22卷 436-444页

作者：郭锐 Zhang Zhenmiao Zhao Jingyi Ning Chao Li Bingliang Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityKey Laboratory of Advanced Forging & Stamping Technology and Science ( Yanshan University) Lianyungang Tianming Equipment Co. Ltd

Different from the traditional hydraulic oil cooling method,a new type of constant temperature oil tank cooling system based on semiconductor refrigeration technology is designed. This paper studies the principle of semiconductor refrigeration and establishes a heat transfer model. Semiconductor cooler on piping refrigeration is simulated,and influence of the parameters on the outlet temperature,such as pipe pressure difference of inlet and outlet,pipe length,pipe radius,are gotten,and then hydraulic tank semiconductor refrigeration system is proposed. The semiconductor refrigeration system can control temperature at 37 ± 1°C.

关键词： refrigeration system constant temperature control semiconductor refrigeration technology hydraulic tank simulated analysis experimental study

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Process of back pressure deep drawing with solid granule medium on sheet metal

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Journal of Central South University 2014年第7期21卷 2617-2626页

作者：董国疆赵长财曹秒艳 College of Vehicles and Energy Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education of China (Yanshan University) National Engineering Research Center for Equipment and Technology of Cold Strip Rolling (Yanshan University)

The experimental die apparatus of the solid granules medium forming on sheet metal was designed and *** parts,such as conical,parabolic,cylindrical and square-box-shaped components,were successfully trial-produced as *** to the analysis of the changing trends of the cross-section shape and the wall thickness during the process,it can be found that the shape of the free deformation zone of the sheet metal,which is the most critical thinning area,can be described as an approximately spherical *** to this forming feature,back pressure deep drawing technology with solid granules medium on sheet metal was proposed to restrain drastic thinning at the bottom of the part through the joint friction effect of solid granules medium,the back pressure tringle and the sheet ***,the deep drawing limit of the sheet metal is significantly *** order to fabricate thin-walled rotary parts with great drawing ratio and complex cross-sections,a finite element model based on the material property test of the solid granules medium was established to optimize the scheme of the back pressure deep *** effects on the forming performance of sheet metal from back pressure load and the approach of blank holding control were analyzed through this model.

关键词： solid granules medium forming drawing sheet metal finite element simulation

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Effect of temperature on the dispersion of graphene in graphene reinforced aluminum matrix composite 4

Effect of temperature on the dispersion of graphene in graph...

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2020 4th International Conference on Material science and technology, ICMST 2020

作者： Wang, Qiang Sun, Qingze Chen, Shengyong Key Laboratory of Advanced Forging and Stamping Technology and Science of Ministry of Education Yanshan University Qinhuangdao066004 China

The influence of hot pressing temperature on the dispersion of graphene (GR) in GR reinforced aluminum matrix composites was investigate. The micro structure s of the sample were observed by optical microscope, scanning electron microscopy and energy dispersion spectrum, respectively. The temperature is hold at 640-750°C, and the interval is 10°C. The results show that GR is mainly distributed at the grain boundary at 640°C. And GR is dispersed in the aluminum matrix, without obvious agglomeration at the temperature from 670°C to 680°C. However, GR is agglomerated in the aluminum matrix and has obvious regional differentiation at 690-750°C, in which the concentrated area of GR is in the middle of the sample, and the dilution area in the rest. © 2020 Institute of Physics Publishing. All rights reserved.

关键词： Graphene

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Configuration Synthesis and Lightweight Networking of Deployable Mechanism Based on a Novel Pyramid Module

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 294-310页

作者： Jinwei Guo Jianliang He Guoxing Zhang Yongsheng Zhao Yundou Xu School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao 066004China Key Laboratory of Advanced Forging and Stamping Technology and Science of Ministry of National Education Yanshan UniversityQinhuangdao 066004China

Deployable mechanism with preferable deployable performance,strong expansibility,and lightweight has attracted much attention because of their potential in aerospace.A basic deployable pyramid unit with good deployability and expandability is proposed to construct a sizeable deployable ***,the basic unit folding principle and expansion method is *** configuration synthesis method of adding constraint chains of spatial closed-loop mechanism is used to synthesize the basic ***,the degree of freedom of the basic unit is analyzed using the screw theory and the link dismantling ***,the three-dimensional models of the pyramid unit,expansion unit,and array unit are established,and the folding motion simulation analysis is carried *** on the number of components,weight reduction rate,and deployable rate,the performance characteristics of the three types of mechanisms are described in ***,prototypes of the pyramid unit,combination unit,and expansion unit are developed to verify further the correctness of the configuration synthesis based on the *** proposed deployable mechanism provides aference for the design and application of antennas with a large aperture,high deployable rate,and *** has a good application prospect in the aerospace field.

关键词： Pyramid unit Deployable mechanism Configuration synthesis Structural design Lightweight networking

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