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DESIGN OF HYDRAULIC SYSTEM FOR WATER-ASSISTED INJECTION MOLDING

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DESIGN OF HYDRAULIC SYSTEM FOR WATER-ASSISTED INJECTION MOLD...

第七届海内外青年设计与制造科学会议

作者： Zhou Hua Zhang Zengmeng and Yang Huayong state key laboratory of fluid power transmission and control zhejiang university {2.

＜正＞Water-assisted injection molding （WAIM） is the newest way to mould hollow plastic parts. Compared with the gas-assisted injection molding （GAIM）, WAIM has advantages of shorter cooling times, larger part dimensions with thinner uniform residual wall, smoother inner part surface and more economical process medium. The present WAIM equipments show disadvantages of inefficiency and the install capacity of a typical system is no less than 2.kW with injection pressure 2. MPa and a small flow rate 60 L/min. A new water hydraulic system is designed for WAIM to make the water injection flow rate reach 12. L/min and the pressure rise from 3 MPa to 2. MPa stepwise in no more than two seconds. Accumulator is used to save energy for intermittent work cycle of large-flow injection and small-flow maintaining pressure. Supercharger is applied in the system to lift the pressure. And a method based on differential pressure control is provided to regulate the pressure when the accumulator discharges. The backpressure of one low-pressure chamber of supercharger is controlled by a water hydraulic proportional pressure relief valve to drop faster than the pressure of the accumulator. The water injection pressure can be increased as demand under the differential pressure control strategy. AMESim simulation is done with the designed parameters on this system. The simulation results indicate that the performance parameters can reach the desirable effect. The install capacity of the hydraulic system is reduced from the value 50 kW of typical system to 5 kW in the same operating mode.

关键词： Water-assisted injection molding Water hydraulic Proportional pressure control AMESim simulation

A MIMO Nonlinear Robust controller for Work-Class ROVs Positioning and Trajectory Tracking control

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A MIMO Nonlinear Robust Controller for Work-Class ROVs Posit...

2.11 Chinese control and Decision Conference（CCDC）

作者： Kangwu Zhu and Linyi Gu are with the state key Lab of {2. power transmission and control,zhejiang university,hangzhou,zhejiang 31002.,china.

In this paper,for the positioning and trajectory tracking control of work-class ROVs with parameter uncertainties and unknown disturbances,a systematically MIMO nonlinear robust controller design method based on adaptive backstepping technique and sliding control is *** Lyapunov stability design method,the locally asymptotically stability of closed-loop control system has been *** effectiveness of controller has been demonstrated by simulation *** simulation results on a work-class ROV proved that the proposed control method has good control performance,and the controller is robust to parameter uncertainties and unknown disturbances.

关键词： Backstepping Sliding control Nonlinear control Work-class ROV Underwater vehicles

Stochastic stability of quasi-integrable Hamiltonian systems with time delay by using Lyapunov function method

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中国科学:技术科学 2010年第2期 217-217页

作者： LING Quan1, JIN XiaoLing1 & HUANG ZhiLong2.1 Department of mechanics, zhejiang university, {2., china 2.state key laboratory of fluid power transmission and control, zhejiang university, {2., china

The asymptotic Lyapunov stability of one quasi-integrable Hamiltonian system with time-delayed feedback control is studied by using Lyapunov functions and stochastic averaging method. First, a quasi-integrable Hamiltonian system with time-delayed feedback control subjected to Gaussian white noise excitation is approximated by a quasi-integrable Hamiltonian system without time delay. Then, stochastic averaging method for quasi-integrable Hamiltonian system is used to reduce the dimension of the original system, and after that the Lyapunov function of the averaged It? equation is taken as the optimal linear combination of the corresponding independent first integrals in involution. Finally, the stability of the system is determined by using the largest eigenvalue of the linearized system. Two examples are used to illustrate the proposed procedure and the effects of delayed time on the Lyapunov stability are discussed as well.

关键词： Lyapunov stability Lyapunov function time delay stochastic averaging

基于栅格地图的移动机器人完全遍历算法——矩形分解法

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机械工程学报 2004年第10期40卷 56-61页

作者：田春颖刘瑜冯申坤朱世强浙江大学流体传动及控制国家重点实验室杭州310027

提出移动机器人的一种新的完全遍历算法:矩形分解算法。首先通过机器人环境学习建立栅格地图,对环境中的障碍物实行矩形化建模。而后应用矩形化模型中的关键点将环境分解成为矩形块,最后在这个分块环境的拓扑图中寻找到一条Hamilton路径... 详细信息

提出移动机器人的一种新的完全遍历算法:矩形分解算法。首先通过机器人环境学习建立栅格地图,对环境中的障碍物实行矩形化建模。而后应用矩形化模型中的关键点将环境分解成为矩形块,最后在这个分块环境的拓扑图中寻找到一条Hamilton路径,机器人沿此路径即可实现对环境的完全遍历。为处理复杂的局部情况,又提出基于模板的局部环境处理算法。矩形算法的优点在于机器人可以实现完全自主的复杂环境遍历,并且可以处理未知障碍,从而使算法适合于任意非结构化的工作环境。

关键词：矩形分解算法 Hamilton路径完全遍历栅格地图移动机器人

RESEARCH ON THE SIX DEGREES OF FREEDOM VEHICLE MOTION SIMULATOR

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RESEARCH ON THE SIX DEGREES OF FREEDOM VEHICLE MOTION SIMULA...

第四届流体传动国际会议

作者： Wang Xuanyin, Liu Rong, Jia Guangzheng, Cheng Jia The state key laboratory of fluid power transmission and control, zhejiang university Post Code: {2., hangzhou, china

In this paper, a six degrees of freedom (6 DOF) vehicle motion simulator has been designed. The theoretic and experimental work has been done to the serve system, which uses the four-way valve to control the asymmetric hydraulic cylinder. The result proves that the platform can smoothly move. The synergetic ability of each DOF is good and its performance meets the requirement of the Vehicle motion simulation.

关键词： 6-DOF Stewart Platform Vehicle Motion Simulator

Research on particle size distribution in rectangular turbulent channel flow

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Research on particle size distribution in rectangular turbul...

第九届国际水动力学会议

作者： Fu-jun Gan 1 Jian-zhong Lin 1 2. state key laboratory of fluid power transmission and control zhejiang university 2.College of Metrology and Measurement Engineering {2. Jiliang university hangzhou {2.

Large eddy simulations of threedimensional particle-laden turbulent channel flow are performed for Re = *** flow results are validated using the experimental data and good agreements are *** is employed to deal with PGDE,which describes PSD,involving the effect of shearinduced coagulation,which is greatly affected by the effects of turbulent transport and preferential concentration,represented by radial relative velocity and radial distribution function,*** with four different stokes number are considered to study the above effects on the evolution of *** the results,the distributions of particle number concentration,polydispersity,particle diameter are detailed discussed.

关键词： turbulent channel flow large eddy simulation Taylor-series expansion moment method relative velocity preferential concentration.

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电脉冲消除45钢淬火件的残余应力

浙江大学学报（工学版） 2012年第8期46卷 1407-1411页

作者：郑建毅何闻施彦彬浙江大学流体传动及控制国家重点实验室浙江省先进制造技术重点实验室现代制造工程研究所浙江杭州310027 厦门大学机电工程系福建厦门361005

为了研究电脉冲消除金属材料内部残余应力的效果,通过储能电容器放电产生高能电脉冲,对淬火后的45优质碳素结构钢冷轧薄板件进行放电处理,采用小孔法测定电脉冲处理前后试样内残余应力的变化规律.用于电脉冲处理的脉冲电流为指数衰减的... 详细信息

为了研究电脉冲消除金属材料内部残余应力的效果,通过储能电容器放电产生高能电脉冲,对淬火后的45优质碳素结构钢冷轧薄板件进行放电处理,采用小孔法测定电脉冲处理前后试样内残余应力的变化规律.用于电脉冲处理的脉冲电流为指数衰减的振荡波形,同时满足第一个主峰的电流密度为12.2.A/mm2.单次处理的振荡脉冲持续时间小于0.8ms.试验结果表明,经过电脉冲处理后,45钢淬火件中2.主方向残余应力的幅值均出现较为显著的降低,且两者都出现均化效果.

关键词：电脉冲 45钢残余应力小孔法

Compensation for time-delayed feedback bang-bang control of quasi-integrable Hamiltonian systems

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中国科学:技术科学 2010年第3期 338-338页

作者： LIU ZhongHua1 & ZHU WeiQiu2.1 Department of Civil Engineering,Xiamen university,Xiamen 361005,china 2.Department of {2.,state key laboratory of fluid power transmission and control,zhejiang university,hangzhou 31002.,china

The stochastic averaging method for quasi-integrable Hamiltonian systems with time-delayed feedback bang-bang control is first ***,two time delay compensation methods,namely the method of changing control force amplitude (CFA) and the method of changing control delay time (CDT),are *** conditions applicable to each compensation method are ***,an example is worked out in detail to illustrate the application and effectiveness of the proposed methods and the two compensation methods in combination.

关键词： time-delayed feedback control compensation method bang-bang control quasi-integrable Hamiltonian system

流体黏温特性对液黏调速离合器传动特性的影响

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上海交通大学学报 2011年第11期45卷 1619-1625页

作者：黄家海方文敏邱敏秀浙江大学流体传动及控制国家重点实验室杭州310027 解放军炮兵学院合肥230031

液黏调速离合器主、从动摩擦盘之间存在的转速差会导致油温升高,进而影响其传动性能.以一对摩擦副间隙内流体流场为研究对象(摩擦盘表面无油槽),建立定常、层流条件下的简化数学模型,同时考虑流体黏温特性的影响,运用数值计算方法获得... 详细信息

液黏调速离合器主、从动摩擦盘之间存在的转速差会导致油温升高,进而影响其传动性能.以一对摩擦副间隙内流体流场为研究对象(摩擦盘表面无油槽),建立定常、层流条件下的简化数学模型,同时考虑流体黏温特性的影响,运用数值计算方法获得了流场温度、剪应力及转矩的数值解.在此基础上,搭建了液黏传动实验台进行实验验证研究.结果表明:受流体黏温特性影响,输出转矩与输出转速之间呈非线性关系;当其他工作条件不变时,输出转矩随输入流量的增加而增加,尤其在低输出转速段,转矩增量较明显.

关键词：液黏传动传热数值计算