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Innovative design and optimization of a two-dimensional deployable nine-grid planar antenna mechanism with a flat reflection surface

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Chinese Journal of Aeronautics 2023年第11期36卷 529-550页

作者： Bo CHEN Ze JIANG Xinlu WEI Luyao GUO Xin ZHOU Yundou XU Junjie QIAN Yongsheng ZHAO Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao 066004China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of National Education Yanshan UniversityQinhuangdao 066004China Space Structure and Mechanism Technology Laboratory of China Aerospace Science and Technology Group Co.Ltd Shanghai 201109China Aerospace System Engineering Shanghai Shanghai 201109China

With the development of the aerospace industry,space missions are becoming more complicated and diversified,and there is a demand for antenna mechanisms with a larger physical *** this paper,a planar deployable mechanism is proposed,which can form a flat reflection surface with a small gap between *** this end,a novel large-scale two-dimensional deployable nine-grid planar antenna mechanism is ***,two antenna folding schemes and four supporting mechanism schemes are *** comparison analysis,the antenna configuration scheme with the best comprehensive performance is selected.A kinematic model of the deployable mechanism is established,and its kinematic characteristics are ***,the correctness of the kinematic model is verified by comparing the analytical and simulation results of the kinematic ***,a finite element model of the antenna is *** on the response surface method,the structural parameters of the support rods of the antenna are optimized,and a set of optimized solutions with lightweight and high fundamental frequency characteristics are ***,a prototype of the proposed nine-grid planar antenna is *** feasibility of the deployment principle and the rationality of the designed mechanism are verified by deployment experiments.

关键词： Design optimization Kinematics Planar antenna Structural design Two-dimensional expansion

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Force measurement method and analysis of guide wire in minimally invasive cardiovascular interventional surgery

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Journal of Chemical and Pharmaceutical Research 2014年第1期6卷 266-270页

作者： Yang, Xue Wang, Hongbo Wang, Qiang Wu, Jianshuang Parallel Robot and Mechatronic System Laboratory of Hebei Province China Key Laboratory of Advanced Forging and Stamping Technology and Science of Ministry of Education Yanshan University China

This paper presents a method of detecting the resistant force that acting on the guide wire when it moving into the body blood vessel for minimally invasive cardiovascular interventional surgery operated by a robot system. To learn more about the influenced factors for measured force, some simulations of body blood flow environment have been given. And then some analyses have been worked on blood flow to study whether the parameters of blood flow influence the resistant force measurement results. All of these studies will make us know more about the reliability of this force detecting method and lay the foundation for realizing force feedback in minimally invasive surgery robot system to further improve the system reliability.

关键词： Blood vessels

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Evaluation on Configuration Stiffness of Overconstrained 2R1T Parallel Mechanisms

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 62-82页

作者： Xuejian Ma Zhenghe Xu Yundou Xu Yu Wang Jiantao Yao Yongsheng Zhao 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

Currently,two rotations and one translation(2R1T)three-degree-of-freedom(DOF)parallel mechanisms(PMs)are widely applied in five-DOF hybrid machining ***,there is a lack of an effective method to evaluate the configuration stiffness of mechanisms during the mechanism design *** is a challenge to select appropriate 2R1T PMs with excellent stiffness performance during the design *** the operational status of 2R1T PMs,the bending and torsional stiffness are considered as indices to evaluate PMs'configuration ***,a specific method is proposed to calculate these stiffness ***,the various types of structural and driving stiffness for each branch are assessed and their specific values ***,a rigid-flexible coupled force model for the over-constrained 2R1T PM is established,and the proposed evaluation method is used to analyze the configuration stiffness of the five 2R1T PMs in the entire ***,the driving force and constraint force of each branch in the whole working space are calculated to further elucidate the stiffness evaluating results by using the proposed method *** obtained results demonstrate that the bending and torsional stiffness of the 2RPU/UPR/RPR mechanism along the x and y-directions are larger than the other four mechanisms.

关键词： Parallel mechanism Stiffness Over-constrained Three degrees of freedom

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Prediction of Critical Conditions for Dynamic Recrystallization in 316LN Austenitic Steel

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Journal of Iron and Steel Research International 2016年第3期23卷 238-243页

作者： Xin-gang LIU Li-ge ZHANG Rong-sheng QI Lei CHEN Miao JIN Bao-feng GUO Key Laboratory of Advanced Forging & Stamping Technology and Science(Yanshan University) Ministry of Education of China Yanshan University Library Yanshan University National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University

Hot compression experiments conducted on a Gleeble-3500thermo-mechanical simulator and metallographic observation tests were employed to study the critical conditions of dynamic recrystallization（DRX）of 316 LN austenitic stainless *** true stress-true strain curves of 316 LN were obtained at deformation temperatures ranging from 900℃to 1 200℃and strain rates ranging from 0.001s-1 to *** on the above tests,the critical conditions of DRX were determined and compared with those obtained from work-hardening theory and the Cingara-McQueen flow stress ***,the microstructure was observed to validate the calculated *** ratio of critical strain to peak strain（εc/εp）for 316 LN was determined,and the quantitative relationship between the critical strain and the deformation parameters of 316 LN was *** results demonstrated that the onset of DRX corresponds to the constant normalized strain hardening rate（Γ）,namely,the critical strain hardening rateΓcfor316LN is equal to 0.65.

关键词： 316LN austenitic stainless steel hot deformation dynamic recrystallization critical condition

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General Analytical Shakedown Analysis of a Structure Subjected to Combined Loading with Constant and Cyclic Loads

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Journal of Harbin Institute of technology(New Series) 2017年第3期24卷 67-75页

作者： Zongyuan Zou Baofeng Guo Miao Jin Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education of China Yanshan UniversityQinhuangdao 066004 China

The shakedown behavior of structures subjected to a combined loading of constant and cyclic loads has been well *** some specified problems,shakedown limit loads have been ***,the general effect of combined loading on the structural shakedown has not yet been *** general analytic solution of the elastic shakedown limit load is thus derived for a structure subjected to combined ***'s extended static shakedown theorem for combined loading is *** stress field in equilibrium with the external constant load required in Polizzotto's extended theorem is constructed by subtracting the reference elastic stress field of the peak cyclic load from the elastic-plastic stress field of the combined constant load and peak cyclic *** shakedown condition of the stress field is then derived according to the extended *** the analytical analysis of the shakedown condition,the structural shakedown behavior under combined loading is investigated.A general solution of the shakedown limit load is then derived,and the effects of the combined loading on the shakedown behavior are *** obtained general analytical result is applied to a hollow tension specimen under constant tension and alternating torsion and a plate with a central hole under constant and cyclic *** results are consistent with the solutions reported in the literature.

关键词： elastic-plastic shakedown limit load general analytical solution combined loading

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Study on the health condition monitoring method of hydraulic pump based on convolutional neural network 12

Study on the health condition monitoring method of hydraulic...

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12th International Conference on Measuring technology and Mechatronics Automation, ICMTMA 2020

作者： Sun, Shaowu Sheng, Zhang Jiang, Wanlu Li, Zhenbao Key Laboratory of Advanced Forging and Stamping Technology and Science Yanshan University Qinhuangdao066004 China

ISBN: (纸本)9781728170817

Aiming at the different health states of hydraulic pumps, this paper proposes to use the convolutional neural network to classify and identify the time-frequency images of different volumetric efficiency of hydraulic pumps to realize the health status monitoring of hydraulic pumps. After collecting the vibration signal data of the hydraulic pump, the time-frequency map is formed by short-time Fourier transform, wavelet transform, and Wigner-Will distribution, and then the generated time-frequency map is divided into a training set and a test set, in which the former is used to train the convolutional neural network and the latter is used to verify the recognition result. Finally, it is proved that the convolutional neural network can well identify the different health states of the hydraulic pump, and the recognition rate reaches 99%. © 2020 IEEE.

关键词： Finite element method

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Phase and CCT Diagram of an N-Containing 8%Cr Roller Steel

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Journal of Harbin Institute of technology(New Series) 2013年第6期20卷 112-117页

作者： Shu-Hua Sun Bo Wang Zhen-Hua Wang Yang Gao Ming-Wei Guo Wan-Tang Fu State Key Laboratory of Metastable Materials Science and Technology Yanshan University College of Sciences Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) Ministry of Education of China China First Heavy Industries

The pseudo-equilibrium phase diagram and continuous cooling transformation diagram of an N-containing 8％ Cr roller steel were investigated by using thermodynamic calculation,differential scanning calorimetry,Ⅹ-ray diffraction,expansion method,and so *** equilibrium conditions,the main carbonitrides are MX,M7C3,and M23C6 *** measured Ac1,Ac3,start temperature of martensitic transformation,and M7C3 transformation temperatures are 811,855,324,and 1100 ℃,*** appears at cooling rates ranging from 0.5 to 5 ℃/s and ferrite forms at grain boundaries at a cooling rate lower than 0.5 ℃/***,the effects of adding N and lowering the C content on workability and mechanical properties of common 8％Cr steel were discussed.

关键词： high Cr roller steel phase diagram continuous cooling transformation N alloyingCLC number:TG142.45 Document code:AArticle ID:1005-9113(2013)06-0112-06

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Kinematics and Dynamics Analysis of a Quadruped Walking Robot with Parallel Leg Mechanism

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 881-891页

作者： WANG Hongbo SANG Lingfeng HU Xing ZHANG Dianfan YU Hongnian Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Xi’an University of Architecture and Technology Science and Technology Research Institute Yanshan University School of Design Engineering and ComputingBournemouth University

It is desired to require a walking robot for the elderly and the disabled to have large capacity,high stiffness,stability,***,the existing walking robots cannot achieve these requirements because of the weight-payload ratio and simple ***,Improvement of enhancing capacity and functions of the walking robot is an important research *** to walking requirements and combining modularization and reconfigurable ideas,a quadruped/biped reconfigurable walking robot with parallel leg mechanism is *** proposed robot can be used for both a biped and a quadruped walking *** kinematics and performance analysis of a 3-UPU parallel mechanism which is the basic leg mechanism of a quadruped walking robot are conducted and the structural parameters are *** results show that performance of the walking robot is optimal when the circumradius R,r of the upper and lower platform of leg mechanism are 161.7 mm,57.7 mm,*** on the optimal results,the kinematics and dynamics of the quadruped walking robot in the static walking mode are derived with the application of parallel mechanism and influence coefficient theory,and the optimal coordination distribution of the dynamic load for the quadruped walking robot with over-determinate inputs is analyzed,which solves dynamic load coupling caused by the branches’ constraint of the robot in the walk *** laying a theoretical foundation for development of the prototype,the kinematics and dynamics studies on the quadruped walking robot also boost the theoretical research of the quadruped walking and the practical applications of parallel mechanism.

关键词： walking robot parallel leg mechanism kinematics dynamics over-determinate inputs

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Hydraulic bulging process with axial feedings and strain field of U-shaped metal bellows

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Journal of Central South University 2018年第11期25卷 2712-2721页

作者： HAO Zeng-liang XI Chen-yang HUANG Zhi-heng ZHANG Chun-xiang LUO Jun-ting Education Ministry Key Laboratory of Advanced Forging&Stamping Technology and Science Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Based on the traditional hydraulic bulging process,an improved hydraulic bulging process with axial feeding in the bulging process was *** finite element simulation and experiment of bellows formed by the traditional and improved hydraulic bulging processes were *** grid strain measurement system analysis results of strain and wall thickness distribution of the metal bellows,obtained from simulation and experiment,show that the maximum thinning rates of the wall thickness under the traditional and improved processes were 15%and 10%,*** the wall thickness distribution of the metal bellows formed with improved process was more *** strain values from the root to crown of the waveform increased ***,the strain values were smaller than those of traditional process due to the axial feeding of the improved process in bulging process.

关键词： hydraulic bulging process finite element simulation thinning rate of wall thickness grid strain measurement system

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Experimental Study on Uniaxial Strain Cyclic Behavior of GS-20Mn5 13th

Experimental Study on Uniaxial Strain Cyclic Behavior of GS-...

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13th International Conference on the technology of Plasticity, ICTP 2021

作者： Zou, Zongyuan Han, Shuting Wang, Hongzhong Li, Qun Guo, Baofeng Zhao, Shiyan Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Qinhuangdao China

ISBN: (纸本)9783030753801

Due to the common discontinuity of the structure and non-uniform load, local high stress phenomenon tends to appear in the mechanical structure under repeated loading, and even local small plastic deformation may occur. In this case, the cyclic elastic–plastic mechanical properties of the structural steel are the key elements for the reasonable and accurate assessment of structural safety. In order to study the cyclic mechanical properties of GS-20Mn5, which is a commonly used steel in load-bearing mechanical equipment, corresponding strain cyclic loading tests were performed. The cyclic elastoplastic deformation characteristics under strain-controlled cyclic loading with different strain ratios (R = −1,0.5) are studied, and the cyclic hardening/softening and mean stress relaxation features are revealed. The results show that the cyclic hardening/softening features are affected by the strain amplitude and cycles. This test material tends to show cyclic hardening at higher strain amplitudes. The cyclic stress–strain curve is obtained by the incremental step test, and the corresponding yield strength is about 4.8% larger than that under uniaxial tension. When R = 0.5, the test material exhibits obvious mean stress relaxation. When the strain amplitude is 0.16%, 0.30%, and 0.40%, the mean stress decreases and then stabilizes at about 25 MPa, −3 MPa, and −6 MPa, respectively. For the mechanical equipment made of GS-20Mn5 with local small plastic deformation under cyclic loading, the obtained cyclic mechanical performance of GS-20Mn5 can provide a reference for the analysis and evaluation of the structural safety. © 2021, The Minerals, Metals & Materials Society.

关键词： Plastic deformation

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