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Configuration and Kinematics of a 3-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

2011 World Congress on Engineering and Technology(CET 2011)

作者： Shaofeng Li 1 1.Jiangsu Engineering and Technology Research Center for Microbiology Resource Jiangsu Key Laboratory for Biodiversity and Biotechnology College of life science Nanjing Normal University Nanjing China Yuru Chen 1 2 2.Department of Biotechnology Taizhou College Nanjing Normal University Taizhou China Kewei Dai 3 3.school of Geography science Nanjing Normal University Nanjing China shijie yang 4 4.school of life science and environment College of Yichun Yichun China

Methods for separation of chlorogenic acid in tobacco materials *** liquid chromatography-mass spectrometry （LC-MS） method for identification and analysis of chlorogenic acids from tobacco material has been *** acid （CQA） were isolated by polyamide column chromatography and further purified by silica gel column *** revealed that polyamide is suitable for separation chlorogenic acid from tobacco *** eluant was collected for two-step column chromatography of *** content of chlorogenic acid of the purified product was 40.3%.After further purification by silica gel column chromatography,the content of total chlorogenic acids was 92.2%.The LC-MS results showed that total chlorogenic acids were made up of four components: 5-CQA,3-CQA,4-CQA and *** content of 5-CQA was the most （78.2%） and other three chlorogenic acid derivatives were 1.9%,10.1% and 2.0% respectively.

关键词： tobacco chlorogenic acid polyamide separation liquid chromatography-mass spectrometry (LC-MS)

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 176-188页

作者： Jianjun Zhang Shuai yang Chenglei Liu Xiaohui Wang shijie Guo school of Mechanical Engineering Hebei University of TechnologyTianjin 300401China Key Laboratory of Robot Perception and Human-Machine Fusion Tianjin 300401China

The kinematic equivalent model of an existing ankle-rehabilitation robot is inconsistent with the anatomical structure of the human ankle,which influences the rehabilitation ***,this study equates the human ankle to the UR model and proposes a novel three degrees of freedom(3-DOF)generalized spherical parallel mechanism for ankle *** parallel mechanism has two spherical centers corresponding to the rotation centers of tibiotalar and subtalar *** screw theory,the mobility of the parallel mechanism,which meets the requirements of the human ankle,is *** inverse kinematics are presented,and singularities are identified based on the Jacobian *** workspaces of the parallel mechanism are obtained through the search method and compared with the motion range of the human ankle,which shows that the parallel mechanism can meet the motion demand of ankle ***,based on the motion-force transmissibility,the performance atlases are plotted in the parameter optimal design space,and the optimum parameter is obtained according to the demands of practical *** results show that the parallel mechanism can meet the motion requirements of ankle rehabilitation and has excellent kinematic performance in its rehabilitation range,which provides a theoretical basis for the prototype design and experimental verification.

关键词： Ankle rehabilitation Parallel mechanism Kinematic analysis Parameter optimization

Dynamics Modeling and Parameter Identification for a Coupled-Drive Dual-Arm Nursing Robot

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 243-257页

作者： Hao Lu Zhiqiang yang Deliang Zhu Fei Deng shijie Guo College of Electronic Information and Automation Tianjin University of Science and TechnologyTianjin 300222China Academy for Engineering&Technology Fudan UniversityShanghai 200433China Shanghai Engineering Research Center of AI&Robotics Shanghai 200433China school of Mechanical Engineering Hebei University of TechnologyTianjin 300130China

A dual-arm nursing robot can gently lift patients and transfer them between a bed and a *** its lightweight design,high load-bearing capacity,and smooth surface,the coupled-drive joint is particularly well suited for these ***,the coupled nature of the joint disrupts the direct linear relationship between the input and output torques,posing challenges for dynamic modeling and practical *** study investigated the transmission mechanism of this joint and employed the Lagrangian method to construct a dynamic model of its internal *** on this foundation,the Newton-Euler method was used to develop a dynamic model for the entire robotic arm.A continuously differentiable friction model was incorporated to reduce the vibrations caused by speed transitions to *** experimental method was designed to compensate for gravity,inertia,and modeling errors to identify the parameters of the friction *** method establishes a mapping relationship between the friction force and motor *** addition,a Fourier series-based excitation trajectory was developed to facilitate the identification of the dynamic model parameters of the robotic *** tracking experiments were conducted during the experimental validation phase,demonstrating the high accuracy of the dynamic model and the parameter identification method for the robotic *** study presents a dynamic modeling and parameter identification method for coupled-drive joint robotic arms,thereby establishing a foundation for motion control in humanoid nursing robots.

关键词： Nursing-care robot Coupled-drive joint Dynamic modeling Parameter identification

Enhancing leaching efficiency of ion adsorption rare earths by ameliorating mass transfer effect of rare earth ions by applying an electric field

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Journal of Rare Earths 2024年第1期42卷 172-180,I0006页

作者： Lingbo Zhou Jie yang shijie Kang Xiaojun Wang Hongdong Yu Yinhua Wan Rare Earth Institute University of Science and Technology of ChinaHefei230000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China Jiangxi Institute of Rare Earths Chinese Academy of SciencesGanzhou341000China school of Resources and environment Engineering Jiangxi University of Science and TechnologyGanzhou341000China

Improving the seepage of leaching solution in the ore body and strengthening the mass transfer process of rare earth ions during in-situ leaching are two critical methods to improve the leaching efficiency of rare *** this study,2 wt%MgSO_(4)solution was used for the indoor simulated column leaching experiment on rare earth samples and an electric field was applied at both ends of the *** the effects of different intensities,initial application time and duration of the electric field on the rare earth leaching system and its mechanism were *** results show that compared with the single MgSO_(4)solution leaching,applying an electric field with a strength of 6 V/cm can save the leaching time of 30 min and increase the flow velocity of the rare earth leachate by 26.98%.Under the optimal conditions of applying an electric field with a strength of 6 V/cm for 20 min to the leaching system after10 min of the rare earth leachate flowing out,the leaching efficiency of sample increases from 81.20% to 86.05% with the increase of 4.85%.The mechanism analysis shows that when a direct current electric field is applied to the rare earth leaching system,rare earth ions rapidly change from disorderly movement with the seepage into faster and directional *** addition,the seepage of the leaching solution is also improved due to the increase of the cross-sectional area of the seepage channel,the polarized water molecules migrate directionally by force from the negative pole,and the movement of the hydrogen is generated by the electrolytic *** impo rtantly,based on the principle of in-situ leaching process,the layout of injection holes and deflector holes in this process provides a natural site for the electrode layout of the electric *** the simple equipme nt and the ope ration,the rare earth leaching process with the applied electric field has high feasibility in industrial application.

关键词： Ion adsorption rare earths Leaching system Electric field Mass transfer process Seepage

Endowing low fatigue for elastocaloric effect by refined hierarchical microcomposite in additive manufactured NiTiCuCo alloy

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International Journal of Extreme Manufacturing 2024年第4期6卷 307-322页

作者： Bo Feng Helong Liu Ying yang Hui Shen yang Ren Yinong Liu Lishan Cui Bingmin Huang shijie Hao College of New Energy and Materials China University of PetroleumBeijing 102249People's Republic of China College of Chemical Engineering and environment China University of PetroleumBeijing 102249People's Republic of China Department of Physics City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong Special Administrative Region of ChinaPeople's Republic of China Department of Mechanical Engineering The University of Western AustraliaPerthWA 6009Australia Jiangsu Smart Advanced Material Tech Co. LtdXuzhou 221000People's Republic of China

NiTiCu-based shape memory alloys have been considered as ideal materials for solid-state refrigeration due to their superb cycling stability for elastocaloric ***,the embrittlement and deterioration caused by secondary phase and coarse grains restrict their applications,and it is still challenging since the geometric components are ***,bulk NiTiCuCo parts with excellent forming quality were fabricated by laser powder bed fusion(LPBF)*** as-fabricated alloy exhibits refined three-phases hierarchical microcomposite formed based on the rapid cooling mode of LPBF,composed of intricate dendritic Ti2Ni–NiTi composite and nano Ti2Cu embedded inside the *** configuration endows far superior elastocaloric stability compared to the as-cast *** low fatigue stems from the strong elastic coupling between the interphases with reversible martensite transformation,revealed by in-situ synchrotron high-energy x-ray *** fabrication of NiTiCuCo alloy via LPBF fills the bill of complex geometric structures for elastocaloric NiTiCu *** understanding of interphase micro-coupling could provide the guide for designing LPBF fabricated shape memory-based composites,enabling their applications for special demands on other functionalities.

关键词： NiTiCuCo shape memoryalloy microcomposite high-energyx-raydiffraction laser powderbedfusion

A numerical simulation strategy for a compressor’s underlying axisymmetric characteristic and its application in body force model

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Chinese Journal of Aeronautics 2024年第8期37卷 79-90页

作者： shijie LIU Tianyu PAN Qiushi LI school of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Accurate prediction of the aerodynamic response of a compressor under inlet distortion is crucial for next-generation civil aircraft,such as Boundary Layer Ingestion(BLI)silent ***,research on the Body Force(BF)model plays a significant role in achieving this ***,distorted inlet airflow can lead to varying operating conditions across different spatial locations of the compressor,which may cause some regions to operate outside the stability ***,the accuracy of BF model simulations might be *** address this issue,this paper proposes a numerical simulation strategy for acquiring the steady axisymmetric three-dimensional flow field of a compressor operating at low mass flow rates,which is known as the Underlying Axisymmetric Pressure Rise Characteristic(UAPRC).The proposed simulation accounts for two different rotor speeds of a transonic compressor and identifies initial positions in the flow field where deterioration occurs based on prior experimental ***,simulation results are incorporated into the BF model to replicate hub instability observed in *** results demonstrate that this strategy provides valid predictions of the UAPRC of the compressor,thereby addressing the limitations associated with the BF model.

关键词： Compressor partial instability Performance at low mass flow rates Underlying axisymmetric pressure rise characteristic Novel simulation strategy Body force model

TOFD detection of shallow subsurface defects in aluminum alloy thin plates by half-skip mode-converted wave

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Chinese Journal of Aeronautics 2024年第6期37卷 454-463页

作者： shijie JIN Zhicheng WANG Zhongbing LUO NDT&E Laboratory Dalian University of TechnologyDalian 116085China

Aluminum alloy is widely applied to the aerospace ***,the inspection of thin plates using Time-of-Flight Diffraction(TOFD)technique is restricted by the near-surface dead zone because of the coupling between diffracted longitudinal wave and lateral *** halfskip mode-converted wave is introduced to decrease dead zone and detect defects in aluminum alloy thin plates by increasing ray path and propagation *** quantitative correlation for the diffracted shear wave from longitudinal back-wall wave is deduced in combination with the acoustic path,realizing the accurate location of shallow subsurface *** and experimental results indicate that the dead zone is decreased by 38% by the half-skip mode-converted wave,and the location errors are within 5% for the aluminum alloy plate with a thickness of 7.0 *** to other alternative TOFD techniques,half-skip mode-converted wave has better response amplitude and positioning accuracy,demonstrating strong applicability in TOFD inspection of thin plates.

关键词： Ultrasonic testing Time-of-Flight Diffraction(TOFD) Dead zone Half-skip mode-converted wave Quantitative detection

Is a direct numerical simulation(DNS)of Navier-Stokes equations with small enough grid spacing and time-step definitely reliable/correct?

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Journal of Ocean Engineering and science 2024年第3期9卷 293-310页

作者： shijie Qin Yu yang Yongxiang Huang Xinyu Mei Lipo Wang Shijun Liao school of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Marine environmental science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China UM-SJTU Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering Shanghai 200240China

Turbulence is strongly associated with the vast majority of fluid flows in nature and ***,results given by the direct numerical simulation(DNS)of Navier-Stokes(NS)equations that relate to a famous millennium problem are widely regarded as‘reliable’benchmark solutions of turbulence,as long as grid spacing is fine enough(*** than the minimum Kolmogorov scale)and time-step is small enough,say,satisfying the Courant-Friedrichs-Lewy condition(Courant number<1).Is this really true?In this paper a two-dimensional sustained turbulent Kolmogorov flow driven by an external body force governed by the NS equations under an initial condition with a spatial symmetry is investigated numerically by the two numerical methods with detailed comparisons:one is the traditional DNS,the other is the‘clean numerical simulation’(CNS).In theory,the exact solution must have a kind of spatial symmetry since its initial condition is spatially ***,it is found that numerical noises of the DNS are quickly enlarged to the same level as the‘true’physical solution,which finally destroy the spatial symmetry of the flow *** other words,the DNS results of the turbulent Kolmogorov flow governed by the NS equations are badly polluted *** the contrary,the numerical noise of the CNS is much smaller than the‘true’physical solution of turbulence in a long enough interval of time so that the CNS result is very close to the‘true’physical solution and thus can remain symmetric,which can be used as a benchmark solution for ***,it is found that numerical noise as a kind of artificial tiny disturbances can lead to huge deviations at large scale on the two-dimensional Kolmogorov turbulence governed by the NS equations,not only quantitatively(even in statistics)but also qualitatively(such as spatial symmetry of flow).This highly suggests that fine enough spatial grid spacing with small enough time-step alone could not guarantee the validity of the DNS of

关键词： Kolmogorov flow Statistical stability Computational reliability Clean numerical simulation Artificial numerical noises

Promising real-time fruit and vegetable quality detection technologies applicable to manipulator picking process

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 14-26页

作者： Jintao Feng Qinyi yang Hao Tian Zhipeng Wang shijie Tian Huirong Xu College of Biosystems Engineering and Food science Zhejiang UniversityHangzhou 310058China Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province Hangzhou 310058China

In recent years,worldwide research on fruit and vegetable quality detection technology includes machine vision,spectroscopy,acoustic vibration,tactile sensors,*** technologies have also been gradually applied to fruit and vegetable grading and sorting lines in recent years,greatly improving the income of *** have been numerous reviews of these *** of the published research on fruit and vegetable quality detection technology is still carried out in the *** emphases have been on quality feature extraction,model establishment and experimental *** successful application in the fruit and vegetable sorting production line proves that these studies have high application potential and value,and we look forward to the performance of these sensing technologies in the fruit and vegetable picking ***,in this paper,based on the future highly automated fruit and vegetable picking mode,we will focus on three kinds of fruit and vegetable quality detection technologies including machine vision,tactile sensor and spectroscopy,to provide some reference for future *** there are currently limited cases of detecting quality during the fruit and vegetable picking,experiments performed on prototypes of manipulator,or devices such as Nanocilia sensors,portable spectrometers,etc.,which are compact and convenient to mount on manipulator will be *** tables and mosaics showing the performance of the three technologies in the detection of fruit and vegetable quality over the past five years have been *** performance of each sensing technology was relatively satisfactory in the laboratory in ***,in the picking scenario,there are still many challenges to be *** from industrial environments,agricultural scenarios are complex and *** and vulnerable agricultural products pose another *** development of portable devices and nanomaterials have become important

关键词： fruit and vegetable quality detection machine vision spectroscopy tactile sensors picking scenario

Multi-UAV Collaborative Mission PlanningMethod for Self-Organized Sensor Data Acquisition

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Computers, Materials and Continua 2024年第1期81卷 1529-1563页

作者： yang, shijie Yuan, Jiateng Zhang, Zhipeng Chen, Zhibo Zhang, Hanchao Cui, Xiaohui school of Information science and Technology Beijing Forestry University Beijing 100083 China Engineering Research Center for Forestry-Oriented Intelligent Information Processing of National Forestry and Grassland Administration Beijing 100083 China State Key Laboratory of Efficient Production of Forest Resources Beijing 100083 China Division of Biostatistics Department of Population Heath Grossman School of Medicine New York University New York NY 10016 United States

In recent years, sensor technology has been widely used in the defense and control of sensitive areas in cities, or in various scenarios such as early warning of forest fires, monitoring of forest pests and diseases, and protection of endangered animals. Deploying sensors to collect data and then utilizing unmanned aerial vehicle (UAV) to collect the data stored in the sensors has replaced traditional manual data collection as the dominantmethod. The current strategies for efficient data collection in above scenarios are still imperfect, and the low quality of the collected data and the excessive energy consumed by UAV flights are still the main problems faced in data *** regards this, this paper proposes a multi-UAV mission planning method for self-organized sensor data acquisition by comprehensively utilizing the techniques of self-organized sensor clustering,multi-UAVmission area allocation, and sub-area data acquisition scheme optimization. The improved α-hop clustering method utilizes the average transmission distance to reduce the size of the collection sensors, and the K-Dimensional method is used to form a multi-UAV cooperative workspace, and then, the genetic algorithm is used to trade-off the speed with the age of information (AoI) of the collected information and the energy consumption to form the multi-UAV data collection operation scheme. The combined optimization scheme in paper improves the performance by 95.56% and 58.21%, respectively, compared to the traditional baseline model. In order to verify the excellent generalization and applicability of the proposed method in real scenarios, the simulation test is conducted by introducing the digital elevation model data of the real terrain, and the results show that the relative error values of the proposed method and the performance test of the actual flight of the UAV are within the error interval of ±10%. Then, the advantages and disadvantages of the present method with the existing mainstr

关键词： Unmanned aerial vehicles (UAV)