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ONLINE GRINDING WHEEL WEAR COMPENSATION BY IMAGE BASED MEASURING TECHNIQUES

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Chinese Journal of Mechanical Engineering 2006年第4期19卷 509-513页

作者： WAN Daping hu dejin WU Qi ZHANG Yonghong School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China School of Information and Communication Nanjing University of Information Science ＆ Technology Nanjing 210044 China

Automatic compensation of grinding wheel wear in dry grinding is accomplished by an image based online measurement method. A kind of PC-based charge-coupled device image recognition system is schemed out, which detects the topography changes of the grinding wheel surface. Profile data, which corresponds to the wear and the topography, is measured by using a digital image processing method. The grinding wheel wear is evalualed by analyzing the position deviation of the grinding wheel edge. The online wear compensation is achieved according to the measure results. The precise detection and automatic compensation system is integrated into an open structure CNC curve grinding machine. A practical application is carried out to fulfil the precision curve grinding. The experimental results confirm the benefits of the proposed techniques, and the online detection accuracy is less than 5 um. The grinding machine provides higher precision according to the in-process grinding wheel error compensation.

关键词： Grinding wheel Wear Compensation Online measurement Charge-coupled device (CCD)

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沱沱河地区天然气烃类微渗漏蚀变信息提取

当代化工研究 2024年第1期 110-112页

作者：欧阳德轩刘依明杨天贵胡德金云南格物智联科技有限公司云南650200 西安煤航遥感信息有限公司陕西710000

本文以沱沱河地区为研究区,以天宫1号数据为信息源,在图像预处理的基础上,开展了天然气水合物烃类微渗漏蚀变信息提取工作,为该区天然气水合物勘探提供依据。研究结果显示:碳酸盐岩异常信息主要分布在本区中侏罗统布曲组(J_(2) b)地层中... 详细信息

本文以沱沱河地区为研究区,以天宫1号数据为信息源,在图像预处理的基础上,开展了天然气水合物烃类微渗漏蚀变信息提取工作,为该区天然气水合物勘探提供依据。研究结果显示:碳酸盐岩异常信息主要分布在本区中侏罗统布曲组(J_(2) b)地层中;黏土矿化异常信息主要分布本区中侏罗统夏里组(J_(2) x)地层中;二价铁离子异常信息主要分布中侏罗统夏里组(J_(2) x)地层中;烃类异常信息主要分布本区中侏罗统布曲组(J_(2) b)及中侏罗统夏里组(J_(2) x)地层中。结合岩性组合特征认为中侏罗统布曲组(J_(2) b)及中侏罗统夏里组(J_(2) x)地层是烃类物质存在的潜在区域。

关键词：沱沱河地区天然气水合物烃类微渗漏天宫1号数据

STUDY ON SINGULAR CONFIGURATIONS AND COMPUTER SIMULATION OF 6R ROBOT

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 177-180页

作者： Zhang Kai hu dejin Liu Chengliang School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200030, China School of Mechanical Engineering Shanghai Jiaotong University 上海 200030

When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6R robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.

关键词： Robot Singular configuration Computer simulation

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二次旋转曲面精密磨削原理与运动控制方法

机械工程学报 2014年第13期50卷 178-183页

作者：胡德金上海交通大学机械与动力工程学院上海200240

针对旋转抛物面、旋转双曲面等非球面精密磨削加工技术难题,在旋转球面精密磨削方法研究基础上,提出旋转抛物面、旋转双曲面等非球面的展成与摆动复合的精密磨削新原理,使磨削主轴旋转中心线与曲线上磨削点的法线重合、磨削主轴的摆动... 详细信息

针对旋转抛物面、旋转双曲面等非球面精密磨削加工技术难题,在旋转球面精密磨削方法研究基础上,提出旋转抛物面、旋转双曲面等非球面的展成与摆动复合的精密磨削新原理,使磨削主轴旋转中心线与曲线上磨削点的法线重合、磨削主轴的摆动中心点始终保持在旋转曲面的旋转轴上,从而避免原理性误差,通过理论分析证明该原理的可行性。对非球面展成与摆动复合精密磨削新原理的运动控制模型进行了讨论,构建具有在线自动检测功能的非球面精密磨削样机,应用在线自动检测功能,克服磨削过程中砂轮损耗对磨削精度的影响,实现磨削、检测自动化操作,一次参数设定就可完成整个磨削过程,提高了磨削效率。试验结果表明,磨削精度达到了令人满意的效果。

关键词：二次旋转曲面展成精密磨削运动控制模型在线检测

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硬脆非球面光学镜精密磨削与自适应控制方法

光学学报 2016年第7期36卷 252-259页

作者：胡德金上海交通大学机械与动力工程学院上海200240

针对硬脆非球面光学镜硬度高、型面特殊、加工面积大、加工质量要求高的特点,提出了一种基于法向跟踪的、以圆筒形砂轮端面进行磨削的非球面范成精密加工方法。在此基础上,进一步设计了智能化的实时检测与自适应控制方法。应用这些方法... 详细信息

针对硬脆非球面光学镜硬度高、型面特殊、加工面积大、加工质量要求高的特点,提出了一种基于法向跟踪的、以圆筒形砂轮端面进行磨削的非球面范成精密加工方法。在此基础上,进一步设计了智能化的实时检测与自适应控制方法。应用这些方法实现了磨削运动轨迹的精确控制、砂轮磨损的自动补偿、磨削压力的自动控制、工艺参数的自动调节。实验结果表明:以圆筒砂轮端面进行磨削的、基于法向跟踪的非球面范成精密磨削法可以保证非球面的面形精度,砂轮磨损实时检测与自适应控制方法能提高加工质量和效率。

关键词：光学制造非球面光学镜法向跟踪精密磨削实时检测自适应控制

Smith Predictor Based Robust Rapid Tracking Controller

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武汉理工大学学报 2006年第S1期28卷 210-213页

作者： LIU Hongbin,hu dejin (School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200030,China) School of Mechanical Engineering Shanghai Jiaotong UniversityShanghai 200030China

Precise model is hard to get in real application,a Smith predictor based robust rapid tracking controller for inaccurate model is proposed. Zero phase error feedforward controller which increases system closed-loop dynamics and disturbance observer based Smith feedback control which diminishes model hysteresis and improves stability are integrated. This method is applied in the noncircular machining with piezoelectric ceramic driver. The simulation and experiment show that the performance robustness and stability are well balanced in bandwidth about 200 Hz. The controller can decrease system hysteresis and get good tracking performance for predefined square-wave input signal.

关键词： smith predictor disturbance objection feedforward compensation tracking performance

不锈钢物流管道内表面磁力研磨的回转磁场设计

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机械工程学报 2005年第2期41卷 102-106页

作者：王艳胡德金上海交通大学机械与动力工程学院上海200030

分析了不锈钢物流管道内表面磁力研磨运动轨迹和速度的要求,研究了各种励磁方法及其研磨运动轨迹, 提出了同时产生回转磁场和往复磁场的励磁方法,设计了能实现复杂研磨轨迹的一种新型回转磁场装置,该回转磁场通过磁极轴向分布产生波浪... 详细信息

分析了不锈钢物流管道内表面磁力研磨运动轨迹和速度的要求,研究了各种励磁方法及其研磨运动轨迹, 提出了同时产生回转磁场和往复磁场的励磁方法,设计了能实现复杂研磨轨迹的一种新型回转磁场装置,该回转磁场通过磁极轴向分布产生波浪形研磨条纹,同时完成磁性磨料对工件的周向回转和轴向往复运动,最后用316L 管道进行了回转磁场的材料去除试验。

关键词：物流管道磁力研磨回转磁场往复磁场

一种用于非圆异形孔加工的电磁驱动机构及控制方法研究

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高技术通讯 2005年第12期15卷 36-40页

作者：张凯胡德金南京信息工程大学信息与通信系南京210044 上海交通大学机械与动力学院上海200030

研究了用于非圆异形孔加工的电磁驱动机构及控制方法.为了对镗杆施加径向随动作用力,研制了由电磁定子和电磁转子组成的回转式电磁驱动机构.当改变定子线圈中的控制电流时,可以改变电磁定子与电磁转子之间的电磁驱动力,进而带动镗刀做... 详细信息

研究了用于非圆异形孔加工的电磁驱动机构及控制方法.为了对镗杆施加径向随动作用力,研制了由电磁定子和电磁转子组成的回转式电磁驱动机构.当改变定子线圈中的控制电流时,可以改变电磁定子与电磁转子之间的电磁驱动力,进而带动镗刀做径向微位移.通过电磁驱动力在静态工作点附近的线性化,建立了电磁驱动力与控制电流之间的线性关系,分析了实现电磁驱动力同步控制的方法.对电磁驱动机构进行了动态模拟试验,试验结果表明,随着转子的转动,在转子与定子之间可以形成一个同步旋转的电磁驱动力,实现镗杆中心的径向可控微位移.因此采用本文提出的回转式电磁驱动机构加工非圆异形孔是可行的.

关键词：非圆异形孔电磁转子电磁定子电磁驱动力

The Identification of Phenylalanine Ammonia-Lyase(PAL)Genes from Pinus yunnanensis and an Analysis of Enzyme Activity in vitro

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 503-516页

作者： dejin Mu Lin Chen Heze Wang Zhaoliu hu Sihui Chen Shi Chen Nianhui Cai Yulan Xu Junrong Tang Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Southwest China Southwest Forestry UniversityKunming650224China College of Forestry Southwest Forestry UniversityKunming650224China

Phenylalanine ammonia lyase(PAL)is the rate-limiting and pivotal enzyme of the general phenylpropanoid path-way,but few reports have been found on PAL genes in Pinus *** the present study,three PAL genes were cloned and identiﬁed from *** seedlings for theﬁrst time,namely,PyPAL-1,PyPAL-2,and *** results indicated that the open-reading frames of PyPAL genes were 2184,2157,and 2385 *** tree analysis revealed that PyPALs have high homology with other known PAL genes in other *** vitro enzymatic analysis showed that all three PyPAL recombinant proteins could catalyze the deamination of L-phenylalanine to form trans-cinnamic acid,but only PAL1 and PAL2 can catalyze the conversion of L-tyrosine toρ-coumaric *** PyPAL genes were expressed in different tissues in 1-year-old ***,and such genes had different expression *** study lays a foundation for further understanding of the biosynthesis of secondary metabolites in ***.

关键词： Pinus yunnanensis phenylalanine ammonia-lyase enzyme activity in vitro functional analysis secondary metabolites