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依托一流工程学科建设高校科技智库的难点、路径和策略

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上海交通大学学报（哲学社会科学版） 2024年第4期32卷 79-92页

作者：周薇张海霞柳存根林忠钦上海交通大学上海200240 上海交通大学、中国海洋装备工程科技发展战略研究院上海200240

科技智库是支撑国家科技决策的重要力量,近年来科技智库的建设在全球范围内得到越来越多的重视和加强,其中依托高校成立的科技智库占据重要地位。全球高校科技智库越来越聚焦专业技术领域政策研究,理工类学科在科技智库建设和发展中发... 详细信息

科技智库是支撑国家科技决策的重要力量,近年来科技智库的建设在全球范围内得到越来越多的重视和加强,其中依托高校成立的科技智库占据重要地位。全球高校科技智库越来越聚焦专业技术领域政策研究,理工类学科在科技智库建设和发展中发挥的作用愈加凸显。高水平研究型大学是国家科技创新体系中的重要力量,依托高校建设科技智库既是国家加强高端智库建设的需要,也应成为高校服务国家战略的自觉追求。本研究基于国外高校科技智库发展趋势,针对我国目前依托高校一流工程学科建设科技智库的难点,深入阐述破解发展难题的路径和策略。

关键词：科技智库一流工程学科有组织科研战略科学家发展路径

h-ADAPTIVE ANALYSIS BASED ON MESHLESS LOCAL PETROV-G ALERKIN METHOD WITH B SPlinE WAVELET FOR PLATES AND SHELLS

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Acta Mechanica Solida Sinica 2009年第4期22卷 337-346页

作者： Di Li zhongqin lin School of Transportation and Vehicle Engineering Shandong University of Technology Zibo 255049 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China

Using the two-scale decomposition technique, the h-adaptive meshless local Petrov- Galerkin method for solving Mindlin plate and shell problems is presented. The scaling functions of B spline wavelet are employed as the basis of the moving least square method to construct the meshless interpolation function. Multi-resolution analysis is used to decompose the field variables into high and low scales and the high scale component can commonly represent the gradient of the solution according to inherent characteristics of wavelets. The high scale component in the present method can directly detect high gradient regions of the field variables. The developed adaptive refinement scheme has been applied to simulate actual examples, and the effectiveness of the present adaptive refinement scheme has been verified.

关键词： meshless methods meshless local Petrov-Galerkin method multi-resolution analysis adaptive analysis plate and shell

Forward Dynamics Analysis of the 6-PUS Mechanism Based on Platform-Legs Composite Simulation

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 496-504页

作者： WANG Hao CHEN Genliang lin zhongqin Key Laboratory of Auto-body Engineering in Shanghai City Shanghai Jiao Tong University Shanghai 200240 China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China

The dynamics analysis plays an important role for the control, simulation and optimization of the parallel manipulators. Normally, the Stewart type manipulators have a platform and several legs. The inverse dynamics can be solved efficiently by taking the advantage of such structural characteristics. However, for the forward dynamics analysis, this structural decomposition still faces challenges from both modeling and computation. In this paper, an efficient approach is proposed for the forward dynamics of the 6-PUS manipulator based on the platform-legs composite simulation. By composite method, the dynamics modeling of the parallel manipulator is separated into the forward dynamics of the platform and the kineto-statics of the legs. The global simulation model can be constructed by connecting the predefined platform model and leg models according to the manipulator＇s topology. Thus, the global simulation can be decomposed into the independent calculations of purely algebraic equations and ordinary differential equations （ODEs）, the computational cost can be reduced and the stability of the simulation can be improved. For the purpose of solving the manipulator＇s forward dynamics accurately, the algebraic-loop problem is discussed and a closed form algorithm is proposed. A numerical example of the 6-PUS manipulator is given to demonstrate the effectiveness of the proposed approach. The example results show that the modeling efficiency can be improved and the simulation stability can be ensured for decomposing the system equations into purely algebraic equations and ODEs.

关键词： forward dynamics Gough-Stewart platform simulation

The Effect of Variable Blank-Holder Forces on the Formability of Aluminum Alloy Sheets during Sheet Metal Forming

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上海交通大学学报 2004年第Z2期38卷 54-60页

作者： Sun Chengzhi Chen Guanlong lin zhongqin School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China

In this paper, the effect of variable Blank-holder forces (VBHF) on the strain path during sheet metal forming has been investigated by numerical simulation and experiments. The formability of select aluminum alloy sheet was evaluated by theory prediction of forming limit curve based on the M-K method. The effect of different VBHF on the formability was presented. In order to verify the predictions of strain path, experiments are being carried out using a recently-built multi-points variable blank-holder forces hydraulic press. The results show that large side BHF with small comer BHF during rectangular box deep drawing can improve the formability of the selected aluminum alloy

关键词： sheet metal forming variable blank-holder force strain path forming limit curve

Optimum Selection of Mechanism Type for Heavy Manipulators Based on Particle Swarm Optimization Method

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 763-770页

作者： ZHAO Yong CHEN Genliang WANG Hao lin zhongqin State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai Key Laboratory of Thin-wall Structure Manufacturing Technology Shanghai Jiao Tong University

The mechanism type plays a decisive role in the mechanical performance of robotic manipulators. Feasible mechanism types can be obtained by applying appropriate type synthesis theory, but there is still a lack of effective and efficient methods for the optimum selection among different types of mechanism candidates. This paper presents a new strategy for the purpose of optimum mechanism type selection based on the modified particle swarm optimization method. The concept of sub-swarm is introduced to represent the different mechanisms generated by the type synthesis, and a competitive mechanism is employed between the sub-swarms to reassign their population size according to the relative performances of the mechanism candidates to implement the optimization. Combining with a modular modeling approach for fast calculation of the performance index of the potential candidates, the proposed method is applied to determine the optimum mechanism type among the potential candidates for the desired manipulator. The effectiveness and efficiency of the proposed method is demonstrated through a case study on the optimum selection of mechanism type of a heavy manipulator where six feasible candidates are considered with force capability as the specific performance index. The optimization result shows that the fitness of the optimum mechanism type for the considered heavy manipulator can be up to 0.578 5. This research provides the instruction in optimum selection of mechanism types for robotic manipulators.

关键词： robot manipulators performance analysis type selection particle swarm optimization

Stabilized Multi-domain Simulation Algorithms and Their Application in Simulation Platform for Forging Manipulator

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 92-102页

作者： HUANG Shunzhou ZHAO Yong WANG Hao lin zhongqin State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures Shanghai Jiao Tong University

Most researches focused on the analytical stabilized algorithm for the modular simulation of single domain, e.g., pure mechanical systems. Only little work has been performed on the problem of multi-domain simulation stability influenced by algebraic loops. In this paper, the algebraic loop problem is studied by a composite simulation method to reveal the internal relationship between simulation stability and system topologies and simulation unit models. A stability criterion of multi-domain composite simulation is established, and two algebraic loop compensation algorithms are proposed using numerical iteration and approximate function in multi-domain simulation. The numerical stabilized algorithm is the Newton method for the solution of the set of nonlinear equations, and it is used here in simulation of the system composed of mechanical system and hydraulic system. The approximate stabilized algorithm is the construction of response surface for inputs and outputs of unknown unit model, and it is utilized here in simulation of the system composed of forging system, mechanical and hydraulic system. The effectiveness of the algorithms is verified by a case study of multi-domain simulation for forging system composed of thermoplastic deformation of workpieces, mechanical system and hydraulic system of a manipulator. The system dynamics simulation results show that curves of motion and force are continuous and convergent. This paper presents two algorithms, which are applied to virtual reality simulation of forging process in a simulation platform for a manipulator, and play a key role in simulation efficiency and stability.

关键词： dynamics multi-domain simulation stability algebraic loop

Texture Evolution Induced by Deformation in Aluminum Alloy

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上海交通大学学报 2004年第Z2期38卷 206-211页

作者： Zhao Yixi lin zhongqin Li shuhui Yu zhongqi School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China

The lower formability of aluminum alloy sheets is the inherent characteristic of the material. During material forming processes the material undergoes a complex strain history. In this paper, the effect of crystallographic texture induced by deformation in aluminum sheet is studied. The transformation of crystallographic textures induced by uniaxial tensile, cup drawing and bulge tests was measured through X-ray diffraction and analyzed. The author studied the texture evolution rule under different strain paths. A qualitative relationship between the deformation and texture evolution has been founded.

关键词： texture evolution aluminum alloy deformation strain path

Composite modeling method in dynamics of planar mechanical system

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Science China(Technological Sciences) 2008年第5期51卷 576-590页

作者： WANG Hao lin zhongqin LAI XinMin State key Lab of Mechanical System and Vibration Institute of Automobile EngineeringShanghai Jiaotong UniversityShanghai 200240China

This paper presents a composite modeling method of the forward dynamics in general planar mechanical system. In the modeling process, the system dynamic model is generated by assembling the model units which are kinematical determinate in planar mechanisms rather than the body/joint units in multi-body system. A state space formulation is employed to model both the unit and system models. The validation and feasibility of the method are illustrated by a case study of a four-bar mechanism. The advantage of this method is that the models are easier to reuse and the system is easier to reconfigure. The formulation reveals the relationship between the topology and dynamics of the planar mechanism to some extent.

关键词： planar mechanism dynamics modeling topology

Analytical and Experimental Studies on Critical Blank-holder Forces in Cylindrical cup deep drawing

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上海交通大学学报 2004年第Z2期38卷 101-107页

作者： lin zhongqin Sun Chengzhi Chen Guanlong Yu Haiyan School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China

Based on the plastic deformation theory and energy method, the critical blank-holder forces (BHF) of wrinkling and fracture in the cylindrical cup deep-drawing are analyzed. The verify experiments were performed and compared with the theory analysis results. The predictions agree well with the experiment results. Thus, the validated presenttheoretical analysis model may be applied to determinate the suitable BHF.

关键词： blank-holder force wrinkle limit fracture limit sheet metal forming formability window