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parameter optimization and experiment of the negative pressure precision seed-metering device for wheat

International Journal of Agricultural and Biological Engineering 2024年第1期17卷 154-162页

作者： Yubo Feng Xiaoshun Zhao Jincai Li Huali Yu Hongpeng Zhao Baozhong Yin State Key Laboratory of North China Crop Improvement and Regulation Hebei Agricultural UniversityBaoding 071001HebeiChina College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina College of Plant Protection Hebei Agricultural UniversityBaoding 071001HebeiChina

In order to ensure the most reasonable distribution of wheat seeds in the field to improve seeding quality and uniformity,a set of negative pressure precision seed-metering device was designed,which shares a hollow *** seed-metering device can sow two rows of *** the STAR-CCM+,the analysis of nephogram,vectogram and streamline graph showed that more ideal structural parameters of the seed-metering device are 0.5 mm width of the slit sucking seed(WSS),150-200 mm diameter of the seed-metering disc(DSD),2.0 mm axial depth of air chamber in the seed-metering disc(ADS),and arc-shaped cross-section shape of the ring groove sucking seed(CSGS).Single-factor test on the JPS-12 test-bed analyzed the influence of the CSGS,WSS,DSD,and ADS on the qualified index(Iq),multiple index(Imul),miss index(Imiss)and coefficient of variation of qualified seed spacing(CV).Through the orthogonal on the JPS-12 test-bed,it is found that the influence of vacuum negative pressure and seed-metering device shaft speed is significant on the Iq,Imiss and *** on these,the structural parameters of the seed-metering device were *** DSD is 180 mm,the WSS is 0.7 mm,the ADS is 2.5 mm,and the CSGS is *** optimization seed-metering device was tested on the JPS-12 *** Iq is 86.66%,the Imiss is 5.09%,the Imul is 8.25%,and the CV is 24.50%.These testing results fully coincide with the standard JB/T 10293-2013 Specifications of single seed drill(precision drill).The seed-metering device meets fully the requirements for wheat precision seeding.

关键词： wheat seed-metering device negative pressure precision parameter optimization STAR-CCM+ orthogonal test variance analysis

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Numerical simulation and parameter optimization of Coriolis force scale measurement process based on DEM

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Particuology 2024年第7期90卷 128-139页

作者： Haiting Liu Yong Yang Xiangliang Wang Jiewen Deng Bingbing Wang School of Energy and Power Engineering Northeast Electric Power UniversityJilin132012China CNBM Hefei Mechanical&Electrical Engineering Technology Co.Ltd Hefei230051China

The Coriolis force method is a recently developed and highly regarded direct measurement technique that enables high-precision measurement of bulk *** operational parameters and variations thereof directly influence the measurement accuracy of the *** this study,a measurement correction coefficient is introduced to improve the calculation method for mass flow rate of the *** DEM is employed to simulate the motion of particle groups within the Coriolis force scale under different parameters,and the effects of various structural and operational parameters on the measurement results are *** research findings indicate that a lower rotational speed leads to more stable instantaneous measurement results,although the measurement error is relatively *** the rotational speed exceeds 300 rpm,the measurement error remains within 15%.For materials with a radius of 1–2 mm,the variation range of precision error is approximately 0.4%.Among the structural parameters,the radius of the measurement wheel has the most significant impact on the measurement results,wherein a larger measurement wheel radius corresponds to a smaller measurement *** horizontal angle of the blades follows as the next influential parameter,with a clockwise rotation and a horizontal angle of 30°resulting in a measurement error below 2%.

关键词： parameter optimization Discrete element method Coriolis force scale Measurement error Numerical simulation

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Design and parameter optimization of Zero Position Code Considering Diffraction Based on Deep Learning Generative Adversarial Networks

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Nanomanufacturing and Metrology 2024年第1期7卷 15-27页

作者： Shengtong Wang Linbin Luo Xinghui Li Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Tsinghua-Berkeley Shenzhen Institute Tsinghua UniversityShenzhen 518055China

Absolute measurement has consistently been the primary focus in the development of precision linear and angular displace-ment *** scheme design of binary zero position codes is an important factor for absolute *** and optimizing high-bit zero position codes with over 100 bits face considerable ***,the working parameters of zero position codes[unit code width(b),distance(d),and yaw angle(α)]remarkably affect their post-installation performance,particularly in absolute positioning and limit code application in multi-degree-of-freedom measurement *** study addresses these challenges by proposing a design method for zero position codes that considers diffraction based on generative adversarial networks and aims to explore a design with increased efficiency and accuracy as well as optimization for high-bit zero position ***,the tolerance range of zero positioning per-formance for each working parameter is *** leveraging the adversarial network structure,this study generates the optimization of a 150-bit code and processes the tests of the zero position code by using simulation *** following working parameter ranges for code design are recommended on the basis of theoretical and experimental results:b greater than 10μm,d andαwithin 1000μm and 3490μrad,and avoidance of intervals with sharp changes in the full width at half *** proposed code design and parameter optimization lay a solid foundation for research and engineering appli-cations in absolute measurement field and have considerable potential for generalization and wide applicability.

关键词： Absolute measurement Zero position code Deep learning Generative adversarial networks Tolerance range parameter optimization

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parameter optimization for torsion spring of deployable solar array system with multiple clearance joints considering rigid–flexible coupling dynamics

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Chinese Journal of Aeronautics 2022年第3期35卷 509-524页

作者： Yuanyuan LI Meng LI Yufei LIU Xinyu GENG Chengbo CUI Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China

In this paper,four novel evaluation indices and corresponding hierarchical optimization strategies are proposed for a deployable solar array system considering panel flexibility and joint *** deployable solar array model consists of a rigid main-body,two panels and four key mechanisms,containing torsion spring mechanism,closed cable loop mechanism,latch mechanism and attitude adjustment *** and flexible components are established by Nodal Coordinate Formulation and Absolute Nodal Coordinate Formulation,*** clearance joint model is described by nonlinear contact force model and amendatory Coulomb friction *** latch time,stabilization time,maximum contact force and impulse sum of the contact force of the solar array system are selected as the four novel evaluation indices to represent the complex dynamic responses of a deployable solar array with clearance joints instead of the lock torque widely used in conventional *** eliminate the gross errors caused by the nonlinear and nonsmooth mechanical properties,a hierarchical optimization strategy based on an adaptive simulated annealing algorithm and a nondominated sorting genetic algorithm is adopted for the solar array system with clearance *** indicate that the effects of panel flexibility on the evaluation index responses and design optimization of the solar array system cannot be ***,increasing the weight factor of the stabilization time index of the rigid system may compensate for the differences in optimal results of the rigid–flexible coupling *** may provide some references for optimization design of deployable space mechanisms considering clearance joints.

关键词： Clearance joint Deployable solar array Evaluation index parameter optimization Rigid-flexible coupling dynamics

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parameter optimization and Precision Enhancement of Dual-Coil Eddy Current Sensor

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Journal of Shanghai Jiaotong university(Science) 2023年第5期28卷 596-603页

作者：张振宁刘强吕春峰毛义梅陶卫赵辉 Department of Instrument Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shandong Institute of Space Electronic Technology Yantai 264670ShandongChina College of Engineering Science and Technology Shanghai Ocean UniversityShanghai 201306China

To enhance the measurement precision of eddy current sensor in particular environments such asextreme temperature changes and limited available space in aerospace, we optimized the structural parameters ofthe traditional dual-coil eddy current sensor probe by electromagnetic field analysis and finite element simulationmodeling, and further presented the criteria for determining the optimal coil distance of the dual-coil probe. Thesimulation results are verified by setting up an experimental platform. For the extreme temperature environment,the displacement measurement error caused by the full range temperature variation of the dual-coil sensor underthe optimal distance is less than 21.0% of that of the single-coil sensor. On this basis, we analyzed and verified thethermal stability of the structurally optimized dual-coil eddy current sensor. After temperature compensation,the displacement measurement accuracy can reach 14.9 times more accurate than that of the single-coil *** method proposed in this paper can provide a design reference for the structural optimization of the axialdual-coil eddy current sensor probe.

关键词： eddy current sensor electromagnetic field analysis finite element simulation parameter optimization

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Performance improvement of licklider transmission protocol in complex deep space networks based on parameter optimization

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Chinese Journal of Aeronautics 2023年第5期36卷 406-420页

作者： Guo YU Zhenxing DONG Yan ZHU Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

A reasonable parameter configuration helps improve the data transmission performance of the Licklider Transmission Protocol(LTP).Previous research has focused mainly on parameter optimization for LTP in simplified scenarios with one to two hops or multihop scenarios with a custody mechanism of the Bundle Protocol(BP).However,the research results are not applicable to communications in Complex Deep Space Networks(CDSNs)without the custody mechanism of BP that are more suitable for deep space communications with *** this paper,we propose a model of file delivery time for LTP in *** on the model,we propose a parameter optimization Design Algorithm for LTP(LTP-PODA)of configuring reasonable parameters for *** results show that the accuracy of the proposed model is at least 6.47%higher than that of the previously established models based on simple scenarios,and the proposed model is more suitable for ***,the LTP parameters are optimized by the LTP-PODA algorithm to obtain an optimization *** the optimization plan for LTP improves the protocol transmission performance by at least 18.77%compared with configuring the other parameter configuration plans.

关键词： Complex deep space networks File delivery time model Licklider Transmission Protocol(LTP) Network Performance Network Protocols parameter optimization Performance improvement

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Reinforcement learning based parameter optimization of active disturbance rejection control for autonomous underwater vehicle

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Journal of Systems Engineering and Electronics 2022年第1期33卷 170-179页

作者： SONG Wanping CHEN Zengqiang SUN Mingwei SUN Qinglin College of Artificial Intelligence Nankai UniversityTianjin 300350China Key Laboratory of Intelligent Robotics of Tianjin Nankai UniversityTianjin 300350China

This paper proposes a liner active disturbance rejection control(LADRC) method based on the Q-Learning algorithm of reinforcement learning(RL) to control the six-degree-of-freedom motion of an autonomous underwater vehicle(AUV).The number of controllers is increased to realize AUV motion *** the same time, in order to avoid the oversize of the algorithm, combined with the controlled content, a simplified Q-learning algorithm is constructed to realize the parameter adaptation of the LADRC ***, through the simulation experiment of the controller with fixed parameters and the controller based on the Q-learning algorithm, the rationality of the simplified algorithm, the effectiveness of parameter adaptation, and the unique advantages of the LADRC controller are verified.

关键词： autonomous underwater vehicle(AUV) reinforcement learning(RL) Q-learning linear active disturbance rejection control(LADRC) motion decoupling parameter optimization

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A systematic design of multifunctional lattice structures with energy absorption and phononic bandgap by topology and parameter optimization

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International Journal of Smart and Nano Materials 2023年第3期14卷 265-285页

作者： Hongling Ye Wenjie Shen Weiwei Wang Ran Tao Faculty of Materials and Manufacturing Beijing University of TechnologyBeijingPRChina College of Engineering Peking UniversityBeijing 100871PR China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijingPRChina

Lattice structure can realize excellent multifunctional charac-teristics because of its huge design space,and the cellular configuration directly affects the lattice structural performance and lightweight.A novel energy-absorbing multifunctional lat-tice structure with phononic bandgap is presented by topol-ogy and parameter optimization in this ***,the two-dimensional(2D)cellular configuration is lightweight designed by using independent continuous mapping(ICM)topology optimization *** 2D cell is reconstructed by geo-metric parameters and rotated into a three-dimensional(3D)cell by using chiral shape to achieve ***,the surrogated model with energy absorption as the object and first-order natural frequency as the constraint is estab-lished to optimize a parametric 3D cell based on the Response Surface Methodology(RSM).Finally,the lattice struc-tures are assembled with dodecagonal staggered arrange-ments to avoid the deformation interference among the adjacent *** addition,the lattice structural energy absorp-tion and bandgap characteristics are analyzed and *** to Kelvin lattice structure,the optimal lattice struc-ture shows significant improvement in energy absorption ***,the proposed design also performs well in damping characteristics of the high-frequency and *** lattice structural optimization design framework has great meaning to achieve the equipment structural light-weight and multi-function in the aerospace field.

关键词： Multifunctional lattice structure energy absorption phononic bandgap topology optimization parameter optimization

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Processing parameter optimization of fiber laser beam welding using an ensemble of metamodels and MOABC

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Frontiers of Mechanical Engineering 2022年第4期17卷 243-259页

作者： Jianzhao WU Chaoyong ZHANG Kunlei LIAN Jiahao SUN Shuaikun ZHANG State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering National University of SingaporeSingapore 117575Singapore Walmart Global Technology Walmart Inc.BentonvilleAR 72712USA

In fiber laser beam welding(LBW),the selection of optimal processing parameters is challenging and plays a key role in improving the bead geometry and welding *** study proposes a multi-objective optimization framework by combining an ensemble of metamodels(EMs)with the multi-objective artificial bee colony algorithm(MOABC)to identify the optimal welding *** inverse proportional weighting method that considers the leave-one-out prediction error is presented to construct EM,which incorporates the competitive strengths of three *** constructs the correlation between processing parameters(laser power,welding speed,and distance defocus)and bead geometries(bead width,depth of penetration,neck width,and neck depth)with average errors of 10.95%,7.04%,7.63%,and 8.62%,*** the basis of EM,MOABC is employed to approximate the Pareto front,and verification experiments show that the relative errors are less than 14.67%.Furthermore,the main effect and the interaction effect of processing parameters on bead geometries are *** demonstrate that the proposed EM-MOABC is effective in guiding actual fiber LBW applications.

关键词： laser beam welding parameter optimization metamodel multi-objective

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Analysis of Additional Damping Control Strategy and parameter optimization for Improving Small Signal Stability of VSC-HVDC System

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Energy Engineering 2023年第4期120卷 931-948页

作者： Hui Fang Jingsen Zhou Hanjie Liu Yanxu Wang Hongji Xiang Yechun Xin State Grid Chongqing Electric Power Company Research Institute Chongqing401120China Northeast Electric Power University Jilin132000China

The voltage source converter based high voltage direct current(VSC-HVDC)system is based on voltage source converter,and its control system is more *** affected by the fast control of power electronics,oscillation phenomenon in wide frequency domain may *** address the problem of small signal stability of the VSCHVDC system,a converter control strategy is designed to improve its small signal stability,and the risk of system oscillation is reduced by attaching a damping controller and optimizing the control *** on the modeling of the VSC-HVDC system,the general architecture of the inner and outer loop control of the VSCHVDC converter is established;and the damping controllers for DC control and AC control are designed in the phase-locked loop and the inner and outer loop control parts respectively;the state-space statemodel of the control system is established to analyze its *** the electromagnetic transient simulation model is built on the PSCAD/EMTDC simulation platform to verify the accuracy of the small signal *** influence of the parameters of each control part on the stability of the system is *** main control parts affecting stability are optimized for the phenomenon of oscillation due to changes in operation mode occurring on the AC side due to faults and other reasons,which effectively eliminates system oscillation and improves system small signal stability,providing a certain reference for engineering design.

关键词： VSC-HVDC system small signal modeling eigenvalue analysis parameter optimization

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