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Toward broad optimal output bandwidth dielectric elastomer actuators

Science China(Technological Sciences) 2022年第5期65卷 1137-1148页

作者： CAO ChongJing chen LiJin LI Bo chen guimin NIE ZeDong WANG Lei GAO Xing Research Centre for Medical Robotics and Minimally Invasive Surgical Devices Shenzhen Institute of Advanced Technology(SIAT)Chinese Academy of SciencesShenzhen518055China Shaanxi Key Laboratory of Intelligent Robots School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an710049China

Dielectric elastomer actuators(DEAs)are one of the most promising soft actuation technologies owing to their relatively high power density and electromechanical efficiency enabled by a resonant actuation technique.However,existing DEA designs suffer from a very narrow optimal output bandwidth close to resonance and poor output control capability due to their fixed geometrical configurations.This condition greatly limits their applications in programmable actuation and broad-bandwidth applications.Accordingly,this work developed a novel resonance tunable DEA(RTDEA)design for broad-optimal-output actuation bandwidths that is enabled by an integration of a stiffness and voltage control strategy.This design features a broad resonant frequency adjustment from 84 to 126 Hz and independent tunings of its resonant amplitude and frequency.Parametric studies were conducted to illustrate the fundamental principles behind the resonance tuning strategy,and optimization was performed to maximize the tuning capability.Here,a resonance tuning control strategy is proposed to achieve accurate adjustments of the RTDEA’s resonance based on the stiffness and voltage control strategy.These resonance tunable soft actuators are envisioned to greatly expand DEAs’applications in,for instance,soft robotic locomotion,human–robot communication,and active vibrational control with demands of broad actuation bandwidths and high output performance.

关键词： dielectric elastomer actuators soft robotics soft actuators resonance tuning resonant actuation

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Constrained multiobjective robust optimization of a bistable mechanism for inertial switch

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Science China(Technological Sciences) 2023年第11期66卷 3186-3196页

作者： LIU Min WANG WeiDong ZHU YingMin YUAN YangBo NIU YanXu DONG LinXi WANG chenYing JIANG Kyle chen guimin School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China School of Electronic Information Hangzhou Dianzi UniversityHangzhou 310018China Collaborative Innovation Center of High-End Manufacturing Equipment Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering University of BirminghamBirmingham B152TTUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

This paper proposes an optimization method for finding the optimal design of a bistable mechanism with a desired performance that is robust to structural and material uncertainties.Using interval numbers to characterize the uncertainties in the structural parameters and materials,we present a nonprobabilistic multiobjective optimization model and transform it into a single objective optimization model using a penalty function.The sensitivity of the mechanical performance of bistable structures to uncertain parameters was analyzed,and the design parameters with notable effects on the bistable performance were identified as optimization variables.A neural network-based proxy model for the nonlinear characteristics of the bistable mechanism was established,and its accuracy was validated through finite element outcomes.Based on this model,a two-layer nested genetic algorithm was employed to solve the multiobjective robust optimization problem of the bistable structures with critical forces and a second stable position.The effectiveness of the optimization method was verified by comparing it with the finite element and experimental results.The proposed method was applied in the design of silicon-based inertial switches.

关键词： multiobjective robust optimization uncertainty interval analysis bistable mechanism

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Structural Synthesis of Compliant Metamorphic Mechanisms Based on Adjacency Matrix Operations

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 522-528页

作者： LI Duanling ZHANG Zhonghai chen guimin School of Automation Beijing University of Posts and Telecommunications Beijing 100876 China School ofMechatronics Xidian University Xi ＇an 710071 China

A compliant metamorphic mechanism attributes to a new type of metamorphic mechanisms evolved from rigid metamorphic mechanisms. The structural characteristics and representations of a compliant metamorphic mechanism are different from its rigid counterparts, so does the structural synthesis method. In order to carry out its structural synthesis, a constraint graph representation for topological structure of compliant metamorphic mechanisms is introduced, which can not only represent the structure of a compliant metamorphic mechanism, but also describe the characteristics of its links and kinematic pairs. An adjacency matrix representation of the link relationships in a compliant metamorphic mechanism is presented according to the constraint graph. Then, a method for structural synthesis of compliant metamorphic mechanisms is proposed based on the adjacency matrix operations. The operation rules and the operation procedures of adjacency matrices are described through synthesis of the initial configurations composed of s＋1 links from an s-link mechanism （the final configuration）. The method is demonstrated by synthesizing all the possible four-link compliant metamorphic mechanisms that can transform into a three-link mechanism through combining two of its links. Sixty-five adjacency matrices are obtained in the synthesis, each of which corresponds to a compliant metamorphic mechanism having four links. Therefore, the effectiveness of the method is validated by a specific compliant metamorphic mechanism corresponding to one of the sixty-five adjacency matrices. The structural synthesis method is put into practice as a fully compliant metamorphic hand is presented based on the synthesis results. The synthesis method has the advantages of simple operation rules, clear geometric meanings, ease of programming with matrix operation, and provides an effective method for structural synthesis of compliant metamorphic mechanisms and can be used in the design of new compliant metamorphic mechanisms.

关键词： compliant metamorphic mechanism structural synthesis constraint graph adjacency matrix

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Rationalizing the isolation distance needed for field trials involving genetically modified rapeseed (Brassica napus L.) in China

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Chinese Science Bulletin 2013年第13期58卷 1558-1567页

作者： ZHAO XiangXiang TANG Tang chen guimin LIU FuXia WANG XingLong BU CuiPing LU ChangMing Key Laboratory of Oil Crop Biology of Ministry of Agriculture Oilcrops Research InstituteChinese Academy of Agricultural Sciences Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake Huaiyin Normal University

The isolation distance required for field trials of genetically modified (GM) rapeseed varies widely worldwide, with a 50-400 m distance in most nations contrasting with a minimum 1000-m isolation distance in China. The goal of this study was to evaluate the relevance of current regulations in China regarding the isolation distance needed for GM rapeseed trials. A pollen flow experiment was conducted based on the design of concentric circles, with the GM plants in a 20-m diameter circle at the centre, surrounded by non-GM plants to a distance 60 m from the perimeter of the circle containing GM plants. The rate of pollen flow was the highest at the isolation distance of 0.5 m, where it ranged from 2.3091% to 2.6711%. The general pattern of the pollen flow rate (y) with distance (x) was well described by the equation y = 1.3936x-0.9136 (R 2 = 0.9950). The long-distance pollen flow tested at the isolation distance of 800 m was 0.0018%, which agrees with the theoretical prediction. The results suggested that 300 m, rather than 1000 m, is a reasonable distance to ensure a tolerable threshold of pollen flow (less than 0.01%) under conditions of winter rapeseed production in China.

关键词：转基因油菜籽隔离距离现场试验中国转基因植物花粉流世界范围田间试验

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Design of Passive Constant‑Force End‑Effector for Robotic Polishing of Optical Reflective Mirrors

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 89-97页

作者： Jian Zhang Liangxiao Zhao Lingling Li Fulei Ma guimin chen School of Mechano‑Electrical Engineering Xidian UniversityXi’an 710071China Xi’an Institute of Optics and Precision Mechanics of CAS Xi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Institute of Robotics and Intelligent Systems Xi’an Jiaotong UniversityXi’an 710049China

Polishing plays an indispensable role in optical processing,especially for large-aperture optical reflective mirrors with freeform surfaces.Robotic polishing requires effective control of the contact force between the robot and the mirror during processing.In order to maintain a constant contact force during polishing,traditional polishing robots rely on closed-loop control of air cylinders,whose performances heavily rely on high-fidelity force sensing and real-time control.This paper proposes to employ a compliant constant-force mechanism in the end-effector of a polishing robot to passively maintain a constant force between the robot and the mirror,thus eliminating the requirement for force sensing and closed-loop control.The compliant constant force mechanism utilizing the second bending mode of fixed-guided compliant beams is adopted and elaborated for the passive end-effector.An end-effector providing a constant contact force of 40 N is designed and prototyped.The polishing experiment shows that the passive constant-force end-effector provides stable contact force between the robot and the mirror with fluctuation within 3.43 N,and achieves RMS(Root Mean Square)lower thanλ/10(λ=632.8 nm)of the polished surface of the largeaperture optical reflective mirror.It is concluded that the constant-force compliant mechanism provides a low-cost and reliable solution for force control in robotic polishing.

关键词： Robotic polishing Fixed-guided compliant beam Constant-force compliant mechanism Passive force control

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酒石酸唑吡坦的合成工艺优化

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中国医药工业杂志 2024年第4期55卷 510-514页

作者：鲍广龙张乃华陈庆涛冯中张贵民鲁南贝特制药有限公司药物新制剂研发山东省工程研究中心山东临沂273400 山东新时代药业有限公司山东省药物国际化工程实验室山东临沂273400

文章对酒石酸唑吡坦(1)的合成工艺进行了改进与优化。以乙醛酸(4)为起始原料与乙酸酐反应得到2,2-二乙酰氧基乙酸(5),5经氯化亚砜氯代生成2,2-二乙酰氧基乙酰氯(6),然后6与二甲胺反应制得N,N-二甲基-2,2-二乙酰氧基乙酰胺(7),7经吡啶对... 详细信息

文章对酒石酸唑吡坦(1)的合成工艺进行了改进与优化。以乙醛酸(4)为起始原料与乙酸酐反应得到2,2-二乙酰氧基乙酸(5),5经氯化亚砜氯代生成2,2-二乙酰氧基乙酰氯(6),然后6与二甲胺反应制得N,N-二甲基-2,2-二乙酰氧基乙酰胺(7),7经吡啶对甲苯磺酸盐水解得关键侧链中间体N,N-二甲基-2-氧代乙酰胺(8)。以对甲基苯乙酮(2)为另一起始物料,经溴素溴代后与2-氨基-5-甲基吡啶经“一锅法”合成6-甲基-2-(4-甲基苯基)咪唑[1,2-a]吡啶(3),然后3与8亲核加成制得α-羟基唑吡坦(9),9经三甲基氯硅烷/碘化钠体系一步还原生成唑吡坦(10),最后10与L-(+)-酒石酸成盐制得1,纯度>99.89%,总收率52.4%(以2计)。改进后的工艺稳定、操作简便、生产成本低,适合工业化生产。

关键词：酒石酸唑吡坦镇静催眠药合成工艺制药工艺

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Notch Flexure as Kirigami Cut for Tunable Mechanical Stretchability towards Metamaterial Application

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International Journal of Smart and Nano Materials 2022年第2期13卷 203-217页

作者： Yanqi Yin Yang Yu Bo Li guimin chen State Key Laboratory of Manufacturing System Engineering Shaanxi Key Laboratory of Intelligent RobotsSchool of Mechanical EngineeringXi’an Jiaotong UniversityXi’anShaanxiChina

Kirigami is an art of paper cutting,which can be used in mechanical metamaterials,actuators,and energy absorption based on its deployable and load-deflection characteristics.Traditional cuts with zero width produce undesirable plastic deformation or even tear fracture due to stress concentration in stretching.This study proposes to enlarge the cut width into a notch flexure,which is applied to an orthogonality-cutted kirigami sheet,which buckles out of plane into a 3D configuration patterns under uniaxial tension.The use of compliant beam as the notch makes the stress distribution around the cuts more uniform in both elastic and elastoplastic regime.The experimental and numerical results show that by tuning the geometric parameters of cuts and material properties of the sheets,the trigger condition of 3D patterns can be adjusted.Potential capability of tunable phononic wave propagation in this kirigami-inspired metamaterial is demonstrated.This design methodology offers a theoretical guide for kirigami-based structures.

关键词： Kirigami design compliant mechanism flexural hinge mechanical metamaterials buckling instability

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基于数据挖掘和网络药理学的反流性食管炎用药规律及机制分析

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中医临床研究 2024年第3期16卷 8-15页

作者：苏妙芳梁振钰陈桂敏黑龙江中医药大学黑龙江哈尔滨150040 海南医学院海南海口571101

目的:基于数据挖掘和网络药理学分析数据库文献中治疗反流性食管炎方剂的用药配伍规律及核心中药作用机制。方法:检索中国知网、维普中文科技期刊全文数据库及万方数据库中治疗反流性食管炎的中药处方,使用Excel建立数据集,进行频数分析... 详细信息

目的:基于数据挖掘和网络药理学分析数据库文献中治疗反流性食管炎方剂的用药配伍规律及核心中药作用机制。方法:检索中国知网、维普中文科技期刊全文数据库及万方数据库中治疗反流性食管炎的中药处方,使用Excel建立数据集,进行频数分析,借助SPSS Modeler 18.0、SPSS Statistics 26.0软件进行关联规则和聚类分析。使用中药系统药理学数据库与分析平台(TCMSP)、GeneCards及Metascape等数据库和Cytoscape软件预测中药治疗反流性食管炎的靶点和通路。结果:共纳入386首方剂,包含182味中药,高频中药为甘草、半夏、黄连、柴胡、白芍和吴茱萸等,通过关联规则分析得出置信度和提升度高的药组为柴胡-吴茱萸-黄连,聚类分析得到7个药物组合。核心药组共获得44个活性成分,含靶点基因219个;筛选后得到反流性食管炎相关靶基因1 384个,匹配后得到共同靶基因98个。通过分析得到丝氨酸/苏氨酸蛋白激酶1(Akt Serine/Threonine Kinase 1,AKT1)、血管内皮生长因子A(Vascular Endothelial Growth Factor A,VEGFA)、白细胞介素(Interleukin,IL)-6等为治疗反流性食管炎的关键靶点,靶点通路富集结果发现癌症相关通路、糖尿病并发症中的晚期糖基化终末产物-晚期糖基化终末产物受体信号通路、乙型肝炎等为主要通路,涉及对无机物的反应、细胞对氮化合物的反应、激酶结合、细胞因子受体结合等生物功能。槲皮素、异鼠李素、山柰酚等成分可能发挥主要的治疗作用。结论:本研究初步探索出近年来中医药治疗反流性食管炎的组方用药规律及3味核心中药的作用成分、靶点及通路,为反流性食管炎的临床治疗和新药研究提供理论依据。

关键词：反流性食管炎数据挖掘网络药理学用药规律作用机制

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正常妊娠孕妇血流动力学参数的变化及其与孕妇基本特征的相关性

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中华妇产科杂志 2024年第5期59卷 375-382页

作者：黄真轩李桂民郑晓芳吴文诗魏宋荃张红霞王永陈敦金余琳广州医科大学附属第三医院妇产科、广州重症孕产妇救治中心、广东省产科重大疾病重点实验室广州510145 深圳市中西医结合医院产科深圳518104

目的探讨正常妊娠孕妇血流动力学参数正常参考范围的变化及其与孕妇基本特征的关系。方法前瞻性纳入2023年1至12月在广州医科大学附属第三医院规律产前检查的健康孕妇共598例,采用无创血流动力学监测仪检测孕妇的血流动力学参数随孕周... 详细信息

目的探讨正常妊娠孕妇血流动力学参数正常参考范围的变化及其与孕妇基本特征的关系。方法前瞻性纳入2023年1至12月在广州医科大学附属第三医院规律产前检查的健康孕妇共598例,采用无创血流动力学监测仪检测孕妇的血流动力学参数随孕周的变化情况,包括心输出量、每搏输出量、胸液水平、外周血管阻力、平均动脉压、心率。使用限制性立方样条模型分析血流动力学参数与孕妇基本特征,包括年龄、身高、体重之间的关系。结果(1)心输出量(r=0.155,P31岁,外周血管阻力、平均动脉压呈上升趋势。结论正常妊娠孕妇的血流动力学参数受其身高、体重、年龄的影响,倡导妊娠期合理控制体重、适龄婚育。

关键词：妊娠血流动力学心排血量血管阻力孕妇

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A Torsion-Bending Antagonistic Bistable Actuator Enables Untethered Crawling and Swimming of Miniature Robots

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Research 2023年第4期2023卷 609-618页

作者： Nan Hu Bo Li Ruiyu Bai Kai Xie guimin chen State Key Laboratory for Manufacturing Systems Engineering and Shaanxi Key Laboratory of Intelligent Robots School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Aerospace Science and Technology Xidian UniversityXi’an 710126China

Miniature robots show great potential in exploring narrow and confined spaces to perform various tasks,but many applications are limited by the dependence of these robots on electrical or pneumatic tethers to power supplies outboard.Developing an onboard actuator that is small in size and powerful enough to carry all the components onboard is a major challenge to eliminate the need for a tether.Bistability can trigger a dramatic energy release during switching between the 2 stable states,thus providing a promising way to overcome the intrinsic limitation of insufficient power of small actuators.In this work,the antagonistic action between torsional deflection and bending deflection in a lamina emergent torsional joint is utilized to achieve bistability,yielding a buckling-free bistable design.The unique configuration of this bistable design enables integrating of a single bending electroactive artificial muscle in the structure to form a compact,self-switching bistable actuator.A low-voltage ionic polymer-metal composites artificial muscle is employed,yielding a bistable actuator capable of generating an instantaneous angular velocity exceeding 300°/s by a 3.75-V voltage.Two untethered robotic demonstrations using the bistable actuator are presented,including a crawling robot(gross weight of 2.7 g,including actuator,battery,and on-board circuit)that can generate a maximum instantaneous velocity of 40 mm/s and a swimming robot equipped with a pair of origami-inspired paddles that swims breaststroke.The low-voltage bistable actuator shows potential for achieving autonomous motion of various fully untethered miniature robots.

关键词： robot yielding torsional

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