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一类少自由度并联构型装备运动学标定方法研究

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中国科学（E辑） 2003年第9期33卷 829-838页

作者：黄田唐国宝李思维李亚 d.g.chetwynd d.J.Whitehouse 天津大学机械工程学院天津300072 School of Engineering University of WarwickCoventry CV4 7ALUK

以一种外副驱动含平行四边形支链的三平动自由度并联机床为对象,研究少自由度并联构型装备运动学标定方法。首先建立末端可控与非可控位姿误差与结构误差的映射关系,并据此构造出具有分层递阶格式的参数辨识模型。针对少自由度并联机构... 详细信息

以一种外副驱动含平行四边形支链的三平动自由度并联机床为对象,研究少自由度并联构型装备运动学标定方法。首先建立末端可控与非可控位姿误差与结构误差的映射关系,并据此构造出具有分层递阶格式的参数辨识模型。针对少自由度并联机构的特点,提出一种通过修正系统输入实施误差软件补偿的方法,并通过实验验证其有效性。

关键词：少自由度并联构型装备运动学标定方法误差建模参数辨识精度标定并联机床

一种三自由度并联机构几何误差建模、灵敏度分析及装配工艺设计

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中国科学（E辑） 2002年第5期32卷 628-635页

作者：黄田李亚李思维唐国宝赵兴玉 d.J.Whitehouse d.g.chetwynd 天津大学机械工程学院天津300072 School of Engineering University of WarwickCoventry CV4 7ALUK

以一类含平行四边形支链的三平动自由度并联机构为对象,利用空间矢量链分析方法,构造出末端位置和姿态误差与几何误差之间的映射关系,明确揭示出影响这种机构末端不可补偿误差的几何误差源,并借助灵敏度分析提出抑制该类误差的装配工艺... 详细信息

以一类含平行四边形支链的三平动自由度并联机构为对象,利用空间矢量链分析方法,构造出末端位置和姿态误差与几何误差之间的映射关系,明确揭示出影响这种机构末端不可补偿误差的几何误差源,并借助灵敏度分析提出抑制该类误差的装配工艺.研究成果已应用于一台并联机床主模块的研制,并对指导同类装备的设计与制造具有普遍的意义.

关键词：并联机构误差建模敏度分析装配工艺

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Tricept机械手静刚度解析建模方法

机械工程学报 2008年第8期44卷 13-19页

作者：王友渔黄田 chetwynd d g HU S J 天津大学机械工程学院天津300072 中国空间技术研究院北京100094 华威大学工学院英国考文垂CV4 7AL 密执安大学机械工程系美国安阿伯MI 48109

以Tricept机械手的3自由度球坐标型并联机构为例,提出含恰约束支链的球坐标型并联构型装备静刚度解析建模方法。该方法首先借助子结构综合思想将末端执行器位姿变形分解为无约束主动支链的拉压变形、恰约束支链的弯曲变形及其扭转变形3... 详细信息

以Tricept机械手的3自由度球坐标型并联机构为例,提出含恰约束支链的球坐标型并联构型装备静刚度解析建模方法。该方法首先借助子结构综合思想将末端执行器位姿变形分解为无约束主动支链的拉压变形、恰约束支链的弯曲变形及其扭转变形3个部分,然后利用虚功原理和结构矩阵法建立各子结构系统的静柔度模型,最后借助线性叠加原理组集整机末端静柔度模型。在建模过程中,侧重研究恰约束支链弯曲剐度以及铰链刚度的建模方法。在此基础上,考察了Tricept机械手中3自由度并联机构静刚度在工作空间中的变化规律,并借助全局性能指标评价了主要构件柔度对整机柔度的贡献。

关键词：并联构型装备静刚度

5自由度大工作空间/支链行程比混联机械手的概念设计与尺度综合

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机械工程学报 2007年第6期43卷 14-20页

作者：刘海涛黄田 chetwynd d g 李曚天津大学机械工程学院天津300072 华威大学工学院密执安大学机械工程系

研究一类新型5自由度可重构混联机械手的创新设计和尺度综合问题,该机械手模块由一2自由度球面并联机构和一条通过滑移副与之串接的两转动一移动串联运动链组成。该混联机械手由于将定点转动与相对滑移运动解耦,因此具有工作空间/支链... 详细信息

研究一类新型5自由度可重构混联机械手的创新设计和尺度综合问题,该机械手模块由一2自由度球面并联机构和一条通过滑移副与之串接的两转动一移动串联运动链组成。该混联机械手由于将定点转动与相对滑移运动解耦,因此具有工作空间/支链行程比大的特点,适合高速轻载作业,可作为即插即用模块用于搭建不同类型的加工制造装备。在建立2自由度球面并联机构的速度映射模型的基础上,分析该机构的奇异性和各向同性问题,并以速度雅可比矩阵最小奇异值的全域均值为操作性能指标,研究2自由度球面并联机构的尺度综合问题。通过单调性分析揭示出尺度参数对该指标的影响规律,进而将尺度综合问题简化为求解杆长等式约束问题。最后给出一组算例,使该尺度综合方法的有效性得到验证。

关键词：并联机器人可重构性概念设计尺度综合

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Nanoindentation Mechanical Properties and Structural Biomimetic Models of Three Species of Insects Wings

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Journal of Wuhan University of Technology(Materials Science) 2015年第4期30卷 831-839页

作者：佟金 CHANg Zhiyong YANg Xiao ZHANg Jin LIU Xianping chetwynd derek g CHEN donghui 孙霁宇 The Key Laboratory of Engineering Bionics (Ministry of Education China) and the College of Biological and Agricultural EngineeringJilin University The United Automotive Electronic Systems Co. Ltd School of Engineering University of Warwick

Mimicking insect flights were used to design and develop new engineering materials. Although extensive research was done to study various aspects of flying insects. Because the detailed mechanics and underlying principles involved in insect flights remain largely unknown. A systematic study was carried on insect flights by using a combination of several advanced techniques to develop new models for the simulation and analysis of the wing membrane and veins of three types of insect wings, namely dragonfly （Pantala flavescens Fabricius）, honeybee （Apis cerana cerana Fabricius） and fly （Sarcophaga carnaria Linnaeus）. In order to gain insights into the flight mechanics of insects, reverse engineering methods were used to establish three-dimensional geometrical models of the membranous wings, so we can make a comparative analysis. Then nano-mechanical test of the three insect wing membranes was performed to provide experimental parameter values for mechanical models in terms of nano-hardness and elastic modulus. Finally, a computational model was established by using the finite element analysis （ANSYS） to analyze and compare the wings under a variety of simplified load regimes that are concentrated force, uniform line-load and a torque. This work opened up the possibility towards developing an engineering basis for the biomimetic design of thin solid films and 2d advanced engineering composite materials.

关键词： biomimetics membranous wing insect wing models finite element method

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSds)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSds,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSds,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa M.g.Cassiano Roney S.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNS)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Passive electrochemical hydrogen recombiner for hydrogen safety systems:prospects

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Nuclear Science and Techniques 2023年第6期34卷 215-224页

作者： A.V.Avdeenkov d.g.Bessarabov d.g.Zaryugin All Russian Research Institute for Nuclear Power Plants Operation JSC 25 Ferganskaya Str.MoscowRussia109507 HySA Center Faculty of EngineeringNorth-West UniversityPotchefstroom2520South Africa State Atomic Energy Corporation Rosatom 24 Bolshaya Ordynka Str.MoscowRussia119017

This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design *** experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(MEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were *** simplest MEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.

关键词： Recombiner Catalytic ignition Hydrogen explosion safety Hydrogen fuel cell Membrane electrode assembly