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Inertia Match of a 3-RRR Reconfigurable Planar Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 791-799页

作者： shao zhufeng TANG Xiaoqiang CHEN Xu WANG Liping Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

Inertia match of the parallel manipulator means the ratio of the inertial load of the parallel manipulator converted to each actuator shaft and the moment of inertia of the actuator is kept within a reasonable range. Currently there are many studies on parallel manipulators, but few mention inertia parameters and inertia match of parallel manipulators. This paper focuses on the inertia characteristics of the 3-RRR reconfigurable planar parallel manipulator. On the basis of the inverse dynamic formulations deduced with the principle of virtual work, the inertia matrix of the 3-RRR planar parallel manipulator in the actuator space is obtained in algebraic form. Then, by unifying the dimension and averaging diagonal elements of the inertia matrix, the equivalent inertia of the parallel manipulator, which is the inertial load of the parallel manipulator converted to each actuator shaft, is determined. By transforming the inertia problem of the 3-RRR parallel manipulator into that of the serial multi-bar manipulator, the practicality of the equivalent inertia deduced by inverse dynamics is demonstrated. According to the physical meaning of the inertia equation, the manipulator is divided in to three parts. Further analysis is carried out on the contribution of each part to the equivalent inertia and their distributions in the required workspace, revealing that the passive links cannot ignored in calculating the equivalent inertia of the parallel manipulator. Finally, the inertia match for the 3-RRR reconfigurable parallel manipulator under three configurations is accomplished, and reducers are selected. The equivalent inertia calculation and the inertial match results illustrate that the inertia math is a necessary step to the design of the parallel manipulator, and inertia parameters dramatically affect dynamic performances of parallel manipulators. Besides, the equivalent inertia and inertial match principles, proposed in the paper, can be widely applied in the dynamic

关键词： inertia match equivalent inertia inverse dynamics parallel manipulator

Atlas Based Kinematic Optimum Design of the Stewart Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 20-28页

作者： shao zhufeng TANG Xiaoqiang WANG Liping SUN Dengfeng State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University School of Aeronautics and Astronautics Engineering Purdue University

Optimum design is a key approach to make full use of potential advantages of a parallel manipulator. The optimum design of multi-parameter parallel manipulators（more than three design parameters）, such as Stewart manipulator, relies on analysis based and algorithm based optimum design methods, which fall to be accurate or intuitive. To solve this problem and achieve both accurate and intuition, atlas based optimum design of a general Stewart parallel manipulator is established, with rational selection of design parameters. Based on the defined spherical usable workspace（SUW）, primary kinematic performance indices of the Stewart manipulator involving workspace and condition number are introduced and analyzed. Then, corresponding performance atlases are drawn with the established non-dimensional design space, and impact of joint distribution angles on the manipulator performance is analyzed and illustrated. At last, an example on atlas based optimum design of the Stewart manipulator is accomplished to illustrate the optimum design process, considering the end-effector posture. Deduced atlases can be flexibly applied to both quantitative and qualitative analysis to get the desired optimal design for the Stewart manipulator with respect to related performance requirements. Besides, the established optimum design method can be further applied to other multi-parameter parallel manipulators.

关键词： optimum design performance atlas parallel mechanism Stewart

Hybrid position/force control strategy and experiment of the six-cable driven parallel manipulator for the forty-meter aperture radio telescope

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High Technology Letters 2012年第3期18卷 230-237页

作者： Li Jian Tang Xiaoqiang shao zhufeng Yao Rui Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 P. R. China

This paper mainly analyzes a hybrid position/force control strategy and experiment of a six-cable driven parallel manipulator for a forty-meter aperture radio telescope. Through the establishments of a kinematic model, a catenary model and a cable-force characteristics model, a basic method is presented based on preventing the pseudo-drag problem of a flexible cable and realizing the hybrid position/force control for a six-cable driven parallel manipulator, and a hybrid position/force control system is developed. Some specific experiments in two typical velocities for astronomical observations are carried out. Experimental results show that the tracking accuracy is related to the speed of the movement. The desired tracking accuracy of the support system is achieved through an effective hybrid position/force control strategy, the cable forces are controlled effectively, and the pseudo-drag problem of flexible cable is solved. This study establishes the foundation of achieving the harmonious movement of the six-cable driven parallel manipulator, A-B rotating platform and the Stewart fine tuninz olatform.

关键词： large radio telescope six-cable driven parallel manipulator hybrid position/forcecontrol tracking accuracy

State-of-the-art on theories and applications of cable-driven parallel robots

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Frontiers of Mechanical Engineering 2022年第3期17卷 35-57页

作者： Zhaokun ZHANG zhufeng shao Zheng YOU Xiaoqiang TANG Bin ZI Guilin YANG Clément GOSSELIN Stéphane CARO State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-Precision Manufacturing Equipment and Control Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of MichiganAnn ArborMI 48109USA Department of Precision Instrument Tsinghua UniversityBeijing 100084China School of Mechanical Engineering Hefei University of TechnologyHefei 230009China Ningbo Institute of Industrial Technology Chinese Academy of Sciences(CAS)Ningbo 315201China Department of Mechanical Engineering UniversitéLavalQuebec QC G1V 0A6Canada Laboratory of Digital Sciences of Nantes National Centre for Scientific ResearchNantes 44321France

Cable-driven parallel robot(CDPR)is a type of high-performance robot that integrates cable-driven kinematic chains and parallel mechanism *** inherits the high dynamics and heavy load capacities of the parallel mechanism and significantly improves the workspace,cost and energy efficiency *** a result,CDPRs have had irreplaceable roles in industrial and technological fields,such as astronomy,aerospace,logistics,simulators,and *** follow the cutting-edge trend of rigid-flexible fusion,reflect advanced lightweight design concepts,and have become a frontier topic in robotics *** paper summarizes the kernel theories and developments of CDPRs,covering configuration design,cable-force distribution,workspace and stiffness,performance evaluation,optimization,and motion *** modeling,workspace analysis,and cable-force solution are *** and dynamic modeling methods are *** further promote the development,researchers should strengthen the investigation in configuration innovation,rapid calculation of workspace,performance evaluation,stiffness control,and rigid-flexible coupling *** addition,engineering problems such as cable materials,reliability design,and a unified control framework require attention.

关键词： cable-driven parallel robot kinematics optimization dynamics control

The Influence Of Defects on LIDT in Fused Silica by 248mn Laser Pulses

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The Influence Of Defects on LIDT in Fused Silica by 248mn La...

强激光材料与元器件学术研讨会暨激光破坏学术研讨会

作者：王慧 Gao zhixing Bo fu zhufeng shao Wang Yufen China Institute of Atomic Energy

The laser damage character of fused silica is studied *** the distribution of the defects is ***,the relevancy of the laser damage character and the defects is ***,the fluorescence of damage-occurring is *** the resul... 详细信息

关键词： fused silica laser damage defects

来源： cnki会议评论

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重心时变的多级混联支撑系统终端精度分析

机器人 2011年第5期33卷 546-552,562页

作者：柴晓明唐晓强邵珠峰清华大学精密仪器与机械学系北京100084

为保证天文观测的跟踪精度,针对500m口径大型球面射电望远镜(FAST)的多级混联馈源支撑系统因重心实时变化带来的终端馈源接收机位姿误差问题,本文首先构建索并联机构的弹性力学模型,建立馈源舱的重心位置和馈源接收机位姿误差的关系模型... 详细信息

为保证天文观测的跟踪精度,针对500m口径大型球面射电望远镜(FAST)的多级混联馈源支撑系统因重心实时变化带来的终端馈源接收机位姿误差问题,本文首先构建索并联机构的弹性力学模型,建立馈源舱的重心位置和馈源接收机位姿误差的关系模型.然后,研究馈源舱重心的时变规律.最后,采用Newton-Raphson法迭代确定重心时变引起的馈源接收机位姿误差范围.最大位置误差和姿态误差分别达到120mm和1.40°,无法达到天文观测的精度要求,因此在原型机的设计、抑振控制及精度控制时要充分考虑重心变化的影响.

关键词：索并联机构多级混联系统时变重心位姿误差

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八索立式储罐并联机器人设计及性能优化

机械工程学报 2016年第9期52卷 1-8页

作者：王伟方唐晓强邵珠峰清华大学机械工程系北京100084 清华大学摩擦学国家重点实验室北京100084

针对石油化工行业中广泛应用的大型立式储罐检修任务,传统的脚手架、导轨及爬壁机器人等工作平台存在拆装困难、结构复杂或运行速度较低等缺点,有效载荷能力和工作效率受限制。索并联机构具有工作空间大、承载能力强、模块化等优点,在... 详细信息

针对石油化工行业中广泛应用的大型立式储罐检修任务,传统的脚手架、导轨及爬壁机器人等工作平台存在拆装困难、结构复杂或运行速度较低等缺点,有效载荷能力和工作效率受限制。索并联机构具有工作空间大、承载能力强、模块化等优点,在大型立式储罐的检修领域极具应用潜力。提出一种采用四根支撑杆的八索驱动并联机器人工作平台及出索点位置可调的模块化支撑杆设计;建立了索并联机构的运动学模型和平面简化模型,分析机构参数对其工作空间的影响,并针对20 m口径典型立式储罐给出了优化结构参数;结合索牵引并联机器人的工作平台沿不同轨迹运动时索长、索力变化分析,确定了运动规划时优选运动轨迹。

关键词：立式储罐索并联机构设计工作空间运动规划

太极拳练习提高老年人上肢扰动状态下视觉空间能力与姿势稳定性的效果

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中国运动医学杂志 2023年第2期42卷 85-92页

作者：邵珠峰宋祺鹏广州体育学院科学实验中心广东广州510500 山东体育学院运动与健康学院山东济南250102

目的:探讨长期练习太极拳对老年人上肢扰动状态下视觉空间能力和姿势稳定性的影响。方法:18名65~77周岁的具有5年以上太极拳练习经验的太极组老年人和19名无规律体育锻炼经历的对照组老年人,按照要求顺次完成跨步触碰和跨步定位任务。使... 详细信息

目的:探讨长期练习太极拳对老年人上肢扰动状态下视觉空间能力和姿势稳定性的影响。方法:18名65~77周岁的具有5年以上太极拳练习经验的太极组老年人和19名无规律体育锻炼经历的对照组老年人,按照要求顺次完成跨步触碰和跨步定位任务。使用AMTI三维测力台和Vicon红外运动捕捉系统同步采集受试者在任务中的空间定位位置、目标定位差、稳定时、任务用时和手脚耦合系数。结果:太极组受试者相比于对照组,在内外方向(P=0.01,d=0.917)和三维空间(P=0.004,d=1.051)具有更小的目标定位差;在前后(P<0.001,η^(2)_(p)=0.716)和内外(P<0.001,η^(2)_(p)=0.540)方向具有更短的稳定时;在任务中具有更短的任务用时(P=0.026,η^(2)_(p)=0.273)。结论:长期练习太极拳的老年人在上肢扰动状态下具有更好的视觉空间能力与姿势稳定性;长期进行太极拳练习可能降低老年人上肢扰动状态下的跌倒风险。

关键词：太极拳视觉空间能力姿势稳定性

The Polite and Impolite Use of Taboo Words in English

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科技信息(学术研究) 2007年第24期 442-444页

作者： shao zhufeng Wang Junping Linyi Normal University Shandong Province Harbin Institute of Technology at Weihai Shandong Province Linyi Normal University Shandong ProvinceWang Junping Harbin Institute of Technology at Weihai Shandong Province

Due to the sensitive nature of taboo words,generally the use of them is strictly *** this paper the author discusses many different uses of taboo words in English,and argues that taboo words can be used not only impolitely as is generally assumed,but also neutrally and *** criterion of judging the politeness/impoliteness of these linguistic items is the motivation we believed to be behind them.

关键词： taboo politeness impoliteness