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Dynamic Manipulability and Optimization of a Two DOF Parallel Mechanism

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 403-409页

作者： SHAO Hua wang jinsong wang Liping GUAN Liwen Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The dynamic dexterity is an important issue for manipulator design, some indices were proposed for analyzing dynamic dexterity, but they can evaluate the dynamic performance just at one pose in the workspaee of the manipulator, and can＇t be applied to dynamic design expediently. Much work has been done in the kinematic optimization, but the work in the dynamic optimization is much less. A global dynamic condition number index is proposed and applied to the dynamic optimization design the parallel manipulator. This paper deals with the dynamic manipulability and dynamic optimization of a two degree-of-freedom （DOF） parallel manipulator. The particular velocity and particular angular velocity matrices of each moving part about the part＇s pivot point are derived fi＇om the kinematic formulation of the manipulator, and the inertial force and inertial movement are obtained utilizing Newton-Euler formulation, then the inverse dynamic model of the parallel manipulator is proposed based on the virtual work principle. The general inertial ellipsoid and dynamic manipulability ellipsoid are applied to evaluate the dynamic performance of the manipulator, a global dynamic condition number index based on the condition number of general inertial matrix in the workspace is proposed, and then the link lengths of the manipulator is redesigned to optimize the dynamic manipulability by this index. The dynamic manipulability of the origin mechanism and the optimized mechanism are compared, the result shows that the optimized one is much better. The global dynamic condition number index has good effect in evaluating the dynamic dexterity of the whole workspace, and is efficient in the dynamic optimal design of the parallel manipulator.

关键词： dynamic manipulability dynamic optimization parallel manipulator

Dynamic Feedforward Control of a Novel 3-PSP 3-DOF Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 676-684页

作者： HAO Qi GUAN Liwen wang jinsong wang Liping Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China Department of Helicopter Mechanical Engineering Institute of Army Aviation Beijing 101123 China

Parallel manipulators with less than six degrees of freedom （DOF） have been increasingly used in high-speed hybrid machine tools. The structural features of parallel manipulators are dynamic, a characteristic that is particularly significant when these manipulators are used in high-speed machine tools. However, normal kinematic control method cannot satisfy the requirements of the control system. Many researchers use model-based dynamic control methods, such as the dynamic feedforward control method. However, these methods are rarely used in hybrid machine tools because of the complex dynamic model of the parallel manipulator. In order to study the dynamic control method of parallel manipulators, the dynamic feedforward control method is used in the dynamic control system of a 3-PSP （prismatic-spherical-prismatic） 3-DOF spatial parallel manipulator used as a spindle head in a high-speed hybrid machine tool. Using kinematic analysis as basis and the Newton-Euler method, we derive the dynamic model of the parallel manipulator. Furthermore, a model-based dynamic feedforward control system consisting of both kinematic control and dynamic control subsystems is established. The dynamic control subsystem consists of two modules. One is used to eliminate the influence of the dynamic characteristics of high-speed movement, and the other is used to eliminate the dynamic disturbances in the milling process. Finally, the simulation model of the dynamic feedforward control system of the 3-PSP parallel manipulator is constructed in Matlab/Simulink. The simulations of the control system eliminating the influence of the dynamic characteristics and dynamic disturbances are conducted. A comparative study between the simulations and the normal kinematic control method is also *** simulations prove that the dynamic feedforward control method effectively eliminates the influence of the dynamic disturbances and dynamic characteristics of the parallel manipulator on high-speed m

关键词： parallel manipulator dynamic feedforward control high-speed hybrid machine tool

Dimensional Synthesis for 3-PRS Mechanism Based on Identifiability Performance

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 234-240页

作者： HUANG Peng wang jinsong wang Liping QIAN Jie Department of Petroleum Equipment Research Institute of Petroleum Exploration and DevelopmentBeijing 100083China Department of Precision Instruments and Mechanology Tsinghua UniversityBeijing 100084China

Many performance indices for parallel mechanism are put forward in the phase of dimensional synthesis,except for identifiability index,which determines the difficulty of kinematical *** the dimensional parameters are inappropriately selected,the existing methods for optimizing identifiability will not effectively ***,with the aim of studying identifiability optimization in dimensional synthesis for 3-PRS mechanism,kinematics with structural errors is analyzed to provide theoretical bases for kinematical *** through a comparison of two 3-PRS mechanisms with different dimensional parameters,identifiability performance is proved to be necessary and feasible for optimization in the phase of dimensional ***,an index δ is proposed to scale the identifiability *** the index,identifiability analysis and dimensional synthesis simulation in the whole workspace is *** index is verified to be correct and feasible,and based on the index,a procedure of dimensional synthesis,as well as an example set of non-dimensional parameters of 3-PRS mechanism,is *** proposed identifiability index and design method can effectively introduce identifiability optimization into dimensional synthesis,and will obviously benefit later kinematical calibration.

关键词： 3-PRS mechanism dimensional synthesis identifiability performance

Integrative ecology in the era of big data——From observation to prediction

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Science China Earth Sciences 2020年第10期63卷 1429-1442页

作者： Shuli NIU Song wang jinsong wang Jianyang XIA Guirui YU Key Laboratory of Ecosystem Network Observation and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China East China Normal University School of Ecology and Environmental ScienceShanghai 200241China

Most ecological and environmental issues faced by human society can only be solved at the ecosystem,watershed,regional and even global ***,ecological research is developing rapidly towards macro-scale *** the rapid development of observational networks and information technology,the spaceborne-aircraft-ground based observation system is becoming an important feature of ecosystem monitoring in the new *** the gradual formation of the global new-generation observational systems and the rapid expansion of massive multi-source heterogeneous data,ecology has entered the era of big data,big science,and big *** to integrate ecological big data,discover valuable ecological laws and mechanisms,and further expand them to solve eco-environmental issues that closely relate to human development are the major opportunities and challenges in this *** this paper,we systematically summarized the research progresses in ecological big data,reviewed the opportunity and demand of integrative ecology,and further discussed the main approaches of ecological big data integration by using meta-analysis,data mining,and data-model ***,we proposed the prospects and research directions of integrative ecology and suggested that future researches need to integrate big data into land models so as to improve the accuracy of ecological *** can be foreseen that under the background of global change and the rapid development of big data in the future,integrative ecology will be extensively applied and developed to serve the sustainable development of human society.

关键词： Integrative ecology Meta-analysis Data mining Data-model fusion

A hidden translatome in tumors——the coding lncRNAs

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Science China(Life Sciences) 2023年第12期66卷 2755-2772页

作者： jinsong wang Wenna wang Fei Ma Haili Qian State Key Laboratory of Molecular Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Long noncoding RNAs(lncRNAs)have been extensively identified in eukaryotic genomes and have been shown to play critical roles in the development of multiple *** the application and development of ribosome analysis and sequencing technologies,advanced studies have discovered the translation of *** lncRNAs were originally defined as noncoding RNAs,many lncRNAs actually contain small open reading frames that are translated into *** opens a broad area for the functional investigation of ***,we introduce prospective methods and databases for screening lncRNAs with functional *** also summarize the specific lncRNA-encoded proteins and their molecular mechanisms that promote or inhibit ***,the role of lncRNA-encoded peptides/proteins holds promise in cancer research,but some potential challenges remain *** review includes reports on lncRNA-encoded peptides or proteins in cancer,aiming to provide theoretical basis and related references to facilitate the discovery of more functional peptides encoded by lncRNA,and to further develop new anti-cancer therapeutic targets as well as clinical biomarkers of diagnosis and prognosis.

关键词： lncRNA translatome peptide tumor

Optimal design of a new spatial 3-DOF parallel robot with respect to a frame-free index

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Science China(Technological Sciences) 2009年第4期52卷 986-999页

作者： jinsong wang XinJun Liu Chao Wu Department of Precision Instruments Tsinghua University Beijing 100084 China

Optimal design is one of the most important issues in robots. Since the very beginning, the concepts of the Jacobian matrix, manipulability and condition number, which are used successfully in the field of serial robots, have been applied to parallel robots. Unlike serial robots, parallel robots are good for motion/force transmission. Their performance evaluation and design should be correspondingly dif- ferent. This paper is an attempt to optimally design a novel spatial three-degree-of-freedom (3-DOF) parallel robot by using the concept of motion/force transmission. Accordingly, three indices are defined. The suggested indices are independent of any coordinate frame and could be applied to the analysis and design of a parallel robot whose singularities can be identified wholly by using the relative angle between the output and adjacent links, and by using the relative angle between the input and adjacent links.

关键词： optimal design parallel robots index transmission angle motion/force transmission

Interruptible Load Scheduling Model Based on an Improved Chicken Swarm Optimization Algorithm

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CSEE Journal of Power and Energy Systems 2021年第2期7卷 232-240页

作者： jinsong wang Fan Zhang Huanan Liu Jianyong Ding Ciwei Gao Department of Electrical Computerand Systems EngineeringCase Western Reserve UniversityCleveland Ohio 44106USA Department of Electrical Engineering Northeast Electric Power UniversityJilin 132012China School of Electrical Engineering Southeast UniversityNanjing 210096China

With the continuous growth of the tertiary industry and residential loads,balancing the power supply and consumption during peak demand time has become a critical *** studies try to alleviate peak load by increasing power generation on the supply *** to the short duration of peak load,this may cause redundant installation ***,others attempt to shave peak demand by installing energy storage ***,the aforementioned research did not consider interruptible load regulation when optimizing system *** fact,regulating interruptible load has great potential for reducing system peak *** this paper,an interruptible load scheduling model considering the user subsidy rate is first proposed to reduce system peak load and operational *** model has fully addressed the constraints of minimum daily load reduction and user interruption load *** that,by taking a community in Shanghai as an example,the improved chicken swarm optimization algorithm is applied to solve the interruptible load scheduling ***,the simulation results validate the efficacy of the proposed optimization algorithm and indicate the significant advantages of the proposed model in alleviating the peak load and reducing operational costs.

关键词： Demand response improved Chicken Swarm Optimization algorithm interruptible load scheduling model peak load user subsidy rate

Combined method for parallel manipulator configuration design

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High Technology Letters 2005年第3期11卷 250-256页

作者： Guan Liwen（关立文） wang jinsong wang Liping Department of Precision Instrument Engineering Tsinghua University Beijing 100084 P.R. China

Configuration design is an essential, creative and decision-making step m parallel manipulator design process, in which modeling and assembly are iterative and trivial. Combined approach with automatic parametric modeling and automatic assembly is proposed for parallel manipulator configuration design. The design process and key techniques, such as configuration design, configuration verification, poses calculation of all parts in parallel manipulator, virtual assembly and etc., are discussed and demonstrated by an example. A software package is developed for parallel manipulator configuration design based on the proposed method with Visual C＋＋ and UG/OPEN on Unigraphics.

关键词： parallel manipulator combined configuration design automatic parametric modeling automatic assembly

Design and experimental study of the SPKM165, a five-axis serial-parallel kinematic milling machine

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Science China(Technological Sciences) 2011年第5期54卷 1193-1205页

作者： XIE FuGui LIU XinJun ZHANG Hui wang jinsong State Key Laboratory of Tribology & Institute of Manufacturing Engineering Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

A five-axis serial-parallel kinematic milling machine, the SPKM 165, is introduced. This machine consists of a three-degree of-freedom parallel module and a two-degree-of-freedom serial table. The SPKM 165 is capable of five-face machining. A discussion of the inverse kinematics of the five-axis control is provided. A dimensional synthesis procedure is presented in terms of motion/force transmissibility. Finite-element analysis was used to evaluate the stiffness of a CAD model before the machine was manufactured. Kinematic calibration was implemented to improve the accuracy of the end effector. The results of a calibration experiment are presented. The stiffness of the developed machine was then measured. Milling experiments were conducted, and the test piece showed that the developed machine has satisfactory performance.

关键词： serial-parallel kinematic machine dimension synthesis stiffness evaluation kinematic calibration