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A Multi-mode Electronic Load Sensing Control Scheme with Power Limitation and Pressure Cut-off for Mobile Machinery

Chinese Journal of Mechanical Engineering 2023年第1期36卷 157-170页

作者： Min Cheng Bolin Sun Ruqi Ding Bing Xu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing400044China Key Laboratory of Conveyance and Equipment Ministry of EducationEast China Jiaotong UniversityNanchang330052China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310027China

In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are integrated into the electronic controller only from the pump level,leading to the potential instability of the overall system.To solve this problem,a multi-mode electrohydraulic load sensing(MELS)control scheme is proposed especially considering the switching stability from the system level,which includes four working modes of flow control,load sensing,power limitation,and pressure control.Depending on the actual working requirements,the switching rules for the different modes and the switching direction(i.e.,the modes can be switched bilaterally or unilaterally)are defined.The priority of different modes is also defined,from high to low:pressure control,power limitation,load sensing,and flow control.When multiple switching rules are satisfied at the same time,the system switches to the control mode with the highest priority.In addition,the switching stability between flow control and pressure control modes is analyzed,and the controller parameters that guarantee the switching stability are obtained.A comparative study is carried out based on a test rig with a 2-ton hydraulic excavator.The results show that the MELS controller can achieve the control functions of proper flow supplement,power limitation,and pressure cut-off,which has good stability performance when switching between different control modes.This research proposes the MELS control method that realizes the stability of multi-mode switching of the hydraulic system of mobile machinery under different working conditions.

关键词： Hydraulic control Load sensing Multi-Mode Power limitation Mobile machinery

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Compliance motion control of the hydraulic dual-arm manipulator with adaptive mass estimation of unknown object

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Frontiers of Mechanical Engineering 2024年第1期19卷 35-52页

作者： Bolin SUN Min Cheng Ruqi DING Bing XU State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China Key Laboratory of Conveyance and Equipment(ministry of Education) East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Given the limited operating ability of a single robotic arm,dual-arm collaborative operations have become increasingly prominent.Compared with the electrically driven dual-arm manipulator,due to the unknown heavy load,difficulty in measuring contact forces,and control complexity during the closed-chain object transportation task,the hydraulic dual-arm manipulator(HDM)faces more difficulty in accurately tracking the desired motion trajectory,which may cause object deformation or even breakage.To overcome this problem,a compliance motion control method is proposed in this paper for the HDM.The mass parameter of the unknown object is obtained by using an adaptive method based on velocity error.Due to the difficulty in obtaining the actual internal force of the object,the pressure signal from the pressure sensor of the hydraulic system is used to estimate the contact force at the end-effector(EE)of two hydraulic manipulators(HMs).Further,the estimated contact force is used to calculate the actual internal force on the object.Then,a compliance motion controller is designed for HDM closed-chain collaboration.The position and internal force errors of the object are reduced by the feedback of the position,velocity,and internal force errors of the object to achieve the effect of the compliance motion of the HDM,i.e.,to reduce the motion error and internal force of the object.The required velocity and force at the EE of the two HMs,including the position and internal force errors of the object,are inputted into separate position controllers.In addition,the position controllers of the two individual HMs are designed to enable precise motion control by using the virtual decomposition control method.Finally,comparative experiments are carried out on a hydraulic dual-arm test bench.The proposed method is validated by the experimental results,which demonstrate improved object position accuracy and reduced internal force.

关键词： hydraulic dual-arm manipulator compliance motion control unknown object adaptive mass estimation nonlinear control

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Motion control of multi-actuator hydraulic systems for mobile machineries： Recent advancements and future trends

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Frontiers of Mechanical Engineering 2018年第2期13卷 151-166页

作者： Bing XU Min Cheng The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Hangzhou 310027 China The State Key Laboratory of Mechanical Transmissions School of Mechanical Engineering Chongqing University Chongqing 400044 China

This paper presents a survey of recent advancements and upcoming trends in motion control technologies employed in designing multi-actuator hydraulic systems for mobile machineries. Hydraulic systems have been extensively used in mobile machineries due to their superior power density and robustness. However, motion control technologies of multi-actuator hydraulic systems have faced increasing challenges due to stringent emission regulations. In this study, an overview of the evolution of existing throttling control technologies is presented, including open-center and load sensing controls. Recent advancements in energy-saving hydraulic technologies, such as individual metering, displacement, and hybrid controls, are briefly summarized. The impact of energy-saving hydraulic technologies on dynamic perfor- mance and control solutions are also discussed. Then, the advanced operation methods of multi-actuator mobile machineries are reviewed, including coordinated and haptic controls. Finally, challenges and opportunities of advanced motion control technologies are presented by providing an overall consideration of energy efficiency, controllability, cost, reliability, and other aspects.

关键词： motion control electrohydraulic control energy efficiency mobile machineries

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Rational design and synthesis of upconversion luminescence-based optomagnetic multifunctional nanorattles for drug delivery

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Chinese Journal of Chemical Engineering 2021年第10期34卷 286-293页

作者： Xuhua Liang Yanyan Zhao Min Cheng Fei Zhang College of Biology Pharmacy and Food Engineering Shangluo UniversityShangluo 726000China Shaanxi Qinling Industrial Technology Research Institute of Special Biological Resources Shangluo 726000China Shaanxi Tasly Plants Pharmaceutical Co. LtdShangluo 726000China

Optomagnetic multifunctional composite based on upconversion luminescence nanomaterial is regarded as a promising strategy for bioimaging,disease diagnosis and targeted delivery of drugs.To explore a mesoporous nanostructure with excellent water dispersibility and high drug-loading capacity,a novel nanorattle-structured Fe3O4@SiO2@NaYF4:Yb,Er magnetic upconversion nanorattle(MUCNR)was successfully designed by using Fe3O4 as core and NaYF4:Yb,Er nanocrystals as shell.The microstructures and crystal phase of the as-prepared MUCNRs were evaluated by transmission electron microscopy,Xray powder diffraction and N2 adsorption/desorption isotherms.The Kirkendall effect was adapted to explain the formation mechanism of the MUCNRs.The loading content and encapsulation efficiency of doxorubicin hydrochloride(DOX)could reach as high as 18.2%and 60.7%,respectively.Moreover,the DOX loading MUCNR(DOX-MUCNR)system showed excellent sustained drug release and strong p Hdependent performance,which was conducive to drug release at the slightly acidic microenvironment of tumor.Microcalorimetry was used to quantify the interactions between the carrier structure and drug release rate directly.The heat release rates in the heat-flow diagrams are basically consistent with the DOX release rate,thereby showing that microcalorimetry assay not only provides a unique thermodynamic explanation for the structure–activity relationship of Fe3O4@SiO2@NaYF4:Yb,Er MUCNRs but also provides powerful guidance to avoid the blind selection or design of drug carriers.Therefore,our work firmly provided a comprehensive perspective for using Fe3O4@SiO2@NaYF4:Yb,Er MUCNRs as a remarkable magnetic targeted drug carrier.

关键词： Optomagnetic nanocomposite Nanorattle Upconversion luminescence Iron oxide Drug delivery

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Practice of flow control and smart valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第4期23卷 243-246页

作者： Jin-yuan QIAN Wei WU Min Cheng Jun-hui ZHANG Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China Institute of Mechatronics and Control Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Introduction The usual metaphors of“heart”and“throat”indi-cate the importance of pumps and valves in industrial systems including petroleum,chemical,metallurgy,aviation,and aerospace.With the continuous penetra-tion of the industrial internet,the miniaturization,digi-tization,multi-functionalization,and systemization of valves have become very important(Si et al.,2020;Chang et al.,2021;Pang et al.,2021;Bonilla et al.,2022;Yuan et al.,2022;Zhao et al.,2022).

关键词： smart internet flow

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Contracted product of hypermatrices via STP of matrices

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Control Theory and Technology 2023年第3期21卷 265-280页

作者： Daizhan cheng min Meng Xiao Zhang Zhengping Ji Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China

An equivalent definition of hypermatrices is introduced.The matrix expression of hypermatrices is proposed.Using permu-tation matrices,the conversion between different matrix expressions is revealed.The various kinds of contracted products of hypermatrices are realized by semi-tensor products(STP)of matrices via matrix expressions of hypermatrices.

关键词： d-hypermatrix Matrix expression Permutation matrices-Contracted product Semi-tensor product(STP)

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Intramolecular Hydrogen Bond Improved Durability and Kinetics for Zinc‑Organic Batteries

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Nano-Micro Letters 2024年第3期16卷 138-148页

作者： Tianjiang Sun Jun Pan Weijia Zhang Xiaodi Jiang Min Cheng Zhengtai Zha Hong Jin Fan Zhanliang Tao Key Laboratory of Advanced Energy Materials Chemistry(ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityHaihe Laboratory of Sustainable Chemical TransformationsTianjin 300071People’s Republic of China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092People’s Republic of China

Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic batteries.Herein,a high-performance quinone-based polymer(H-PNADBQ)material is designed by introducing an intramolecular hydrogen bonding(HB)strategy.The intramolecular HB(C=O⋯N-H)is formed in the reaction of 1,4-benzoquinone and 1,5-naphthalene diamine,which efficiently reduces the H-PNADBQ solubility and enhances its charge transfer in theory.In situ ultraviolet-visible analysis further reveals the insolubility of H-PNADBQ during the electrochemical cycles,enabling high durability at different current densities.Specifically,the H-PNADBQ electrode with high loading(10 mg cm^(-2))performs a long cycling life at 125 mA g^(-1)(>290 cycles).The H-PNADBQ also shows high rate capability(137.1 mAh g^(−1)at 25 A g^(−1))due to significantly improved kinetics inducted by intramolecular HB.This work provides an efficient approach toward insoluble organic electrode materials.

关键词： Zn-organic batteries H-PNADBQ polymer Intramolecular hydrogen bond Reduced solubility Improvedπ-conjugated level

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High-resolution forward-looking imaging algorithm for missile-borne detectors

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Journal of Systems Engineering and Electronics 2019年第3期30卷 456-466页

作者： cheng cheng GAO min ZHOU Xiaodong Department of Missile Engineering Army Engineering University Shijiazhuang 050003 China Department of Ammunition Engineering Army Engineering University Shijiazhuang 050003 China

Aiming at a novel missile-borne detector in the optional burst height proximity fuze, a self-adaptive high-resolution forward-looking imaging algorithm (SAHRFL-IA) is presented. The echo data are captured by the missile-borne detector in the target regions;thereby the azimuth angulation accuracy at the same distance dimension is improved dynamically. Thus, azimuth information of the targets in the detection area may be obtained accurately. The proposed imaging algorithm breaks through the conventional misconception of merely using azimuth discrimination curves under ideal conditions during monopulse angulation. The real-time echo data from the target region are used to perform error correction for this discrimination curve, and finally the accuracy of the azimuth angulation may reach the optimum at the same distance dimension. A series of experiments demonstrate the validity, reliability and high performance of the proposed imaging algorithm. Azimuth angulation accuracy may reach ten times that of the detection beam width. Meanwhile, the running time of this algorithm satisfies the requirements of missile-borne platforms.

关键词： forward-looking imaging high-resolution missileborne detector self-adaptive radio proximity fuze

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Impacts of the COVID-19 pandemic on consumers’ food safety knowledge and behavior in China

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Journal of Integrative Agriculture 2020年第12期19卷 2926-2936页

作者： min Shi XIANG cheng ZHANG Xiao-heng College of Economics and Management Huazhong Agricultural UniversityWuhan 430070P.R.China Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

This study assesses the impacts of the COVID-19 pandemic on Chinese residents’food safety knowledge and behavior,and explores the possible influence mechanism,namely,focus on media information.The study is based on internet survey data of 1373 residents in China.A series of econometric models are developed to estimate food safety knowledge and behavior of residents.Both the descriptive and econometric results indicate that the existence of COVID-19 cases in a community has a significantly positive effect on residents’food safety knowledge and behavior.Residents focusing on food safety-related information tend to have higher food safety knowledge and practice food safety behavior.When controlling the variable focused on food safety-related information,the marginal effects of the existence of COVID-19 cases in a community on residents’food safety knowledge and behavior significantly decrease.However,the decrease in consumers’food safety knowledge is quite minor.Hence,the COVID-19 pandemic indeed improves Chinese residents’food safety knowledge and behavior,while focus on food safety-related information is an important mechanism for improving food safety behavior.Moreover,the estimation results of the simultaneous equations model reveal that consumers’food safety knowledge has a significant and positive effect on their food safety behavior.Heterogeneous impacts of the COVID-19 pandemic on residents’food safety knowledge and behavior among different regions and income groups are observed.The findings of this study provide evidence that public health events could enhance residents’safety awareness and behavior,while residents’focus on relevant information plays an important role in improving knowledge and impacting behavior.

关键词： food safety knowledge behavior COVID-19

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Effect of thermal induced porosity on high-cycle fatigue and very high-cycle fatigue behaviors of hot-isostatic-pressed Ti-6Al-4V powder components

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Journal of Materials Science & Technology 2022年第3期98卷 177-185页

作者： Min Cheng Zhengguan Lu Jie Wu Ruipeng Guo Junwei Qiao Lei Xu Rui Yang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The present work reports the effect of thermal induced porosity(TIP)on the high-cycle fatigue(HCF)and very high-cycle fatigue(VHCF)behaviors of hot-isostatic-pressed(HIPed)Ti-6Al-4V alloy from gasatomized powder.The results show that the residual pores in the as-HIPed powder compacts present no obvious effect on the HCF life.The regrowth of the residual pores can be observed after solution heat treatment.The pore location ranks the most harmful for the fatigue life compared with the other initiating defects.The maximum stress intensity factors were calculated.The plastic zone size of fine granular area(FGA)is much less than the characteristic size of the microstructure,and the crucial size of the internal pores in this study is about 40μm.The failure types of fatigue specimens in the VHCF regime were classified,and the competition of different failure types was described based on the modified Poisson distribution.

关键词： Titanium alloy Hot isostatic pressing Fatigue life Crack initiation type Porosity

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