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蛇形空间机械臂单个2-DOF关节的运动学标定

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机床与液压 2024年第3期52卷 1-9页

作者：宋国庆赵成浩袁俊杰张忠海何广平北方工业大学机械与材料工程学院北京100144 北京航天测控技术有限公司北京100041

绳索驱动的分段式蛇形空间机械臂通常具有相同结构的模块化关节,能够在狭小空间中灵巧操作,其精度是制约机器人发展的主要因素。为了提高蛇形空间机械臂的位置精度,指导蛇形空间机械臂的精度设计,以单个2-DOF关节为对象,提出一种正则化... 详细信息

绳索驱动的分段式蛇形空间机械臂通常具有相同结构的模块化关节,能够在狭小空间中灵巧操作,其精度是制约机器人发展的主要因素。为了提高蛇形空间机械臂的位置精度,指导蛇形空间机械臂的精度设计,以单个2-DOF关节为对象,提出一种正则化的运动学标定方法。首先,对具有多重映射关系的2-DOF关节的运动学进行分析,通过矩阵全微分理论建立包含所有几何误差参数的误差模型。然后,对2-DOF关节各部件的所有误差源进行灵敏度分析,依据3σ原则和理想的位置精度设计指标指导各部件的公差设计。最后,考虑所有的制造和装配误差,采用正则化方法对2-DOF关节进行误差辨识,用于补偿控制器中的名义运动学模型。结果表明,经过修正后的运动学模型的位置精度提高了50%,验证了运动学标定的有效性。

关键词：运动学误差分析灵敏度分析运动学标定精度设计

Optimal Motion Planning for Differentially Flat Underactuated Mechanical Systems

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Chinese Journal of Mechanical Engineering 2009年第3期22卷 347-354页

作者： he guangping GENG Zhiyong State Key Laboratory for Turbulence and Complex System Peking University Beijing 100871 China Department of Mechanical and Electrical Engineering North China University of Technology Beijing 100041 China

Underactuated mechanical system has less independent inputs than the degrees of freedom（DOF） of the mechanism. The energy efficiency of this class of mechanical systems is an essential problem in practice. On the basis of the sufficient and necessary condition that concludes a single input nonlinear system is differentially flat, it is shown that the flat output of the single input underactuated mechanical system can be obtained by finding a smooth output function such that the relative degree of the system equals to the dimension of the state space. If the flat output of the underactuated system can be solved explicitly, and by constructing a smooth curve with satisfying given boundary conditions in fiat output space, an energy efficiency optimization method is proposed for the motion planning of the differentially flat underactuated mechanical systems. The inertia wheel pendulum is used to verify the proposed optimization method, and some numerical simulations show that the presented optimal motion planning method can efficaciously reduce the energy cost for given control tasks.

关键词： differential flatness underactuated system motion planning optimization

Investigation on the Effect of the Tension Degree of Tracks on the Adsorption Performance of Tracked Wall Climbing Robot

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Journal of Harbin Institute of Technology(New Series) 2023年第1期30卷 52-60页

作者： Shun Xiao guangping he Jiejian Di Jie Zhang Zhonghai Zhang Lin Zhou Department of Mechanical and Electrical Engineering North China University of TechnologyBeijing 100144China Beijing Aerospace Measurement&Control Technology Co. Ltd.Beijing 100041China

In this paper,a new tracked wall climbing robot with permanent magnetic units is designed,and the tension degree of robot’s tracks is found to have a significant impact on the robot’s adsorption *** tracked wall climbing robot is a remotely controlled *** the control devices can be installed on the robot *** the permanent magnetic units are arranged on the light *** order to illustrate the relationship between the tension degree and the adsorption performance,when absorbed on the vertical surface and 180⁃degree inverted surface,the static force analysis of the robot is ***,experiments were demonstrated to prove that higher tension degree of tracks can make adsorption performance better.

关键词： permanent magnetic adsorption track tension degree wall climbing robot

OPTIMAL SYNTheSIS OF PLANAR 4 LIMBS 3-DOF OVERACTUATED PARALLEL MECHANISMS

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 34-38页

作者： he guangping WANG Fengxiang LU Zhen School of Mechanical and Electrical Engineering North China University of Technology Beijing 100041 China School of Automation Science and Electrical Engineering Beihang University Beijing 100083 China

Optimal synthesis of a 3-DOF 4 limbs planar parallel mechanism with actuated redundancy is studied. The kinematics equation of the mechanism is developed and the topology of the mecha-nism is classified. The kinematics and force properties of the mechanisms according to the topologies are compared. Furthermore, a global optimizing formulation is derived from the condition number that is a local index usually used to scaling the manipulability isotropy quantitatively. The optimiza-tion is solved by genetic algorithm. The numerical results show that the topology of the mechanisms can influence the kinematics and force property considerably, and the manipulation dexterity of the mechanisms can be improved distinctly by the given formulations and the suggested optimization algorithm.

关键词： Parallel mechanisms Overactuated Optimization synthesis Isotropy

A Piezoelectrically Driven Microrobot Using a Novel Monolithic Spatial Parallel Mechanism as Its Hip Joint

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Journal of Bionic Engineering 2024年第2期21卷 803-820页

作者： guangping Wu Ziyang Wang Jiaxin Zhao Feng Cui Xinghan Cai National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai200240China Department of Micro-Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Inspired by the fast,agile movements of insects,we present a 1.9 g,4.5 cm in length,piezoelectrically driven,quadrupedal *** microrobot uses a novel spatial parallel mechanism as its hip joint,which consists of two spatially orthogonal slider-crank *** mechanism maps two inputs of two independent actuators to the decoupled swing and lift outputs of a leg,and each leg can produce the closed trajectories in the sagittal plane necessary for robot ***,the kinematics of the transmission are analyzed,and the parameters of the flexure hinges are designed based on geometrical constraints and yield *** hip joints,legs and exoskeletons are integrated into a five-layer standard laminate for monolithic fabrication which is composed of two layers of carbon fiber,two layers of acrylic adhesive and a polyimide *** measured output force(15.97 mN)of each leg is enough to carry half of the robot’s weight,which is necessary for the robot to move *** has been proven that the robot can successfully perform forward and turning *** to the microrobot fabricated with discrete components,the monolithically fabricated microrobot is more capable of maintaining the original direction of locomotion when driven by a forward signal and has a greater speed,whose maximum speed is 25.05 cm/s.

关键词： Insect-like Crawling microrobot Piezoelectric drive Parallel mechanism Monolithic fabrication

从“民族”到“国家”:抗战时期于式玉的边疆考察

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中华文化论坛 2023年第3期 19-30,188页

作者：何广平四川大学国际关系学院/中国西部边疆安全与发展协同创新中心四川成都610066

于式玉多次参与边疆考察,足迹遍及中国北部、西北、西南等地区,但对其边疆研究影响最大的当属抗战时期的甘南拉卜楞考察和川西黑水调查。两次考察都从关注民族开始,进而关怀国家。在拉卜楞地区,于式玉带着“研究民族学”的目的而来,却... 详细信息

于式玉多次参与边疆考察,足迹遍及中国北部、西北、西南等地区,但对其边疆研究影响最大的当属抗战时期的甘南拉卜楞考察和川西黑水调查。两次考察都从关注民族开始,进而关怀国家。在拉卜楞地区,于式玉带着“研究民族学”的目的而来,却投入大量时间精力于边民教育工作;在黑水地区,于式玉因理番县政府的邀请,参与调查黑水族群情况,却对当地政治、经济、教育等领域表现出浓厚的兴趣。这些都是于式玉关注国家、民族(中华民族)的重要表现,也是她推动“边疆”“化成正常的行政区域”,“边民”“变成正常的公民”做出的时代努力。

关键词：于式玉边疆考察民族国家意识

Kinematics Modeling and Motion Planning of Tendon Driven Continuum Manipulators

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Journal of Artificial Intelligence and Technology 2021年第1期1卷 28-36页

作者： Jie Zhang Kang Lu Junjie Yuan Jiejian Di guangping he Department of Mechanical and Electrical Engineering North China University of TechnologyBeijing100144 China

Continuum manipulators have important applications in the human–machine interaction *** kinematics,dynamics,and control issues of the continuum manipulators are rather different from a conventional rigid-link *** the aid of Lie groups theory and exponential coordinate representations,the kinematics of the continuum manipulators with piecewise constant curvatures and actuated by tendons is investigated in this *** the basis of differential kinematics analysis,the complete Jacobian of the continuum manipulators is derived analytically,and then a new motion planning approach,named as“dynamic coordination method”is presented for the multisegments continuum manipulators,which is a class of superredundant *** novel motion planning approach is featured by some appealing properties,and the feasibility of the modeling and the motion planning method is demonstrated by some numerical simulations.

关键词： kinematics motion planning continuum manipulators robots

Effect of drying cracks on swelling and self-healing of bentonite-sand blocks used as engineered barriers for radioactive waste disposal

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1776-1787页

作者： Yu Tan guangping Zhou Huyuan Zhang Xiaoya Li Ping Liu School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University) Ministry of EducationLanzhou730000China Civil and Environmental Engineering University of Wisconsin-MadisonWI53706USA

Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste *** groundwater was prepared to represent the geochemistry of Beishan groundwater,and was used to hydrate the blocks during the swelling pressure and swelling strain measurements,as Beishan is the most promising site for China's *** of the surface cracks was recorded by photography,and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried *** results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater,but not affected by the drying *** maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh *** maximum swelling pressure measured in strong(*** ion strength)Beishan groundwater was 44%of the pressure measured in deionized(DI)water,and the maximum swelling strain was reduced to 23%of the strain measured in DI ***,the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks,as demonstrated by the pictures of surface cracks and CT *** hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable(3.7×higher)to the hydraulic conductivity of the fresh block,indicating the self-healing of drying cracks after hydration and swelling in groundwater.A simplified method of protecting the block with plastic wraps before installation is recommended,since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks.

关键词： Beishan groundwater chemistry Bentonite buffer Drying cracks High-level radioactive waste(HLW) Self-healing Swelling

Adeno-associated virus as a delivery vector for gene therapy of human diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1808-1840页

作者： Jiang-Hui Wang Dominic J.Gessler Wei Zhan Thomas L.Gallagher guangping Gao Horae Gene Therapy Center University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Microbiology and Physiological Systems University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Centre for Eye Research Australia Royal Victorian Eye and Ear HospitalEast MelbourneVIC3002Australia Ophthalmology Department of SurgeryUniversity of MelbourneEast MelbourneVIC3002Australia Department of Neurological Surgery University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Neurosurgery University of MinnesotaMinneapolisMN55455USA Department of Medicine University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Li Weibo Institute for Rare Diseases Research University of Massachusetts Chan Medical SchoolWorcesterMA01605USA

Adeno-associated virus(AAV)has emerged as a pivotal delivery tool in clinical gene therapy owing to its minimal pathogenicity and ability to establish long-term gene expression in different *** AAV(rAAV)has been engineered for enhanced specificity and developed as a tool for treating various ***,as rAAV is being more widely used as a therapy,the increased demand has created challenges for the existing manufacturing *** rAAV-based gene therapy products have received regulatory approval,but there continue to be concerns about safely using high-dose viral therapies in humans,including immune responses and adverse effects such as genotoxicity,hepatotoxicity,thrombotic microangiopathy,and *** this review,we explore AAV biology with an emphasis on current vector engineering strategies and manufacturing *** discuss how rAAVs are being employed in ongoing clinical trials for ocular,neurological,metabolic,hematological,neuromuscular,and cardiovascular diseases as well as *** outline immune responses triggered by rAAV,address associated side effects,and discuss strategies to mitigate these *** hope that discussing recent advancements and current challenges in the field will be a helpful guide for researchers and clinicians navigating the ever-evolving landscape of rAAV-based gene therapy.

关键词： diseases specificity approval