汽车锁扣是保证汽车安全运行的重要部件,针对传统方法测量锁扣铆点不稳定、精度低的缺点,提出了一种基于机器视觉的检测方法;首先进行相机标定,通过预处理消除拍摄影响,接着提取锁扣的几何特征以建立测量坐标系,并对其进行仿射变换以消...汽车锁扣是保证汽车安全运行的重要部件,针对传统方法测量锁扣铆点不稳定、精度低的缺点,提出了一种基于机器视觉的检测方法;首先进行相机标定,通过预处理消除拍摄影响,接着提取锁扣的几何特征以建立测量坐标系,并对其进行仿射变换以消除图像几何失真;然后标定铆点所在区域,设置ROI(regions of interest)使铆点从检测背景中分离出来成为一个独立的图像单元,对其进行梯度锐化以增强图像边缘,并依据ROI自身特点对传统锐化方法进行了改进;最后,采用随机Hough变换分别提取改进前后图像铆点的轮廓,测量铆点直径并进行对比;实验表明,改进后图像铆点直径的测量值更加准确,精度达到0.035mm,满足检测要求。该方法适用于铆点在线高精度检测,具有重要的应用价值。展开更多
点铆过程控制采用模糊控制器和 PI 控制器的混合型结构。模糊控制规则根据点铆手动运行经验总结而成。其控制量选择原则是:误差较大时选择控制量以消除误差为主,误差较小时选择控制量须注意防止超调。其采样时间的选择,受误差变化最大...点铆过程控制采用模糊控制器和 PI 控制器的混合型结构。模糊控制规则根据点铆手动运行经验总结而成。其控制量选择原则是:误差较大时选择控制量以消除误差为主,误差较小时选择控制量须注意防止超调。其采样时间的选择,受误差变化最大值与一次响应过程中控制作用次数两方面的制约。展开更多
Ternary Ⅰ–Ⅲ–Ⅵquantum dots（QDs） of chalcopyrite semiconductors exhibit excellent optical properties in solar cells. In this study, ternary chalcopyrite CuGaS2nanocrystals（2–5 nm） were one-pot anchored on TiO2...Ternary Ⅰ–Ⅲ–Ⅵquantum dots（QDs） of chalcopyrite semiconductors exhibit excellent optical properties in solar cells. In this study, ternary chalcopyrite CuGaS2nanocrystals（2–5 nm） were one-pot anchored on TiO2nanoparticles（TiO2@CGS） without any long ligand. The solar cell with TiO2@CuGaS2/N719 has a power conversion efficiency of7.4%, which is 23% higher than that of monosensitized dye solar cell. Anchoring CuGaS2 QDs on semiconductor nanoparticles to form QDs/dye co-sensitized solar cells is a promising and feasible approach to enhance light absorption,charge carrier generation as well as to facilitate electron injection comparing to conventional mono-dye sensitized solar cells.展开更多
文摘汽车锁扣是保证汽车安全运行的重要部件,针对传统方法测量锁扣铆点不稳定、精度低的缺点,提出了一种基于机器视觉的检测方法;首先进行相机标定,通过预处理消除拍摄影响,接着提取锁扣的几何特征以建立测量坐标系,并对其进行仿射变换以消除图像几何失真;然后标定铆点所在区域,设置ROI(regions of interest)使铆点从检测背景中分离出来成为一个独立的图像单元,对其进行梯度锐化以增强图像边缘,并依据ROI自身特点对传统锐化方法进行了改进;最后,采用随机Hough变换分别提取改进前后图像铆点的轮廓,测量铆点直径并进行对比;实验表明,改进后图像铆点直径的测量值更加准确,精度达到0.035mm,满足检测要求。该方法适用于铆点在线高精度检测,具有重要的应用价值。
基金the financial support from the National Key Research and Development Program of China(2016YFA0201001)the National Natural Science Foundation of China(11627801,51102172 and 11772207)+7 种基金Science and Technology Plan of Shenzhen City(JCYJ20160331191436180)the Leading Talents of Guangdong Province Program(2016LJ06C372)the Natural ScienceFoundation for Outstanding Young Researcher in Hebei Province(E2016210093)the Key Program of Educational Commission of Hebei Province of China(ZD2016022)the Youth Top-notch Talents Supporting Plan of Hebei Provincethe Graduate Innovation Foundation of Shijiazhuang Tiedao UniversityHebei Provincial Key Laboratory of Traffic Engineering materialsHebei Key Discipline Construction Project
文摘Ternary Ⅰ–Ⅲ–Ⅵquantum dots（QDs） of chalcopyrite semiconductors exhibit excellent optical properties in solar cells. In this study, ternary chalcopyrite CuGaS2nanocrystals（2–5 nm） were one-pot anchored on TiO2nanoparticles（TiO2@CGS） without any long ligand. The solar cell with TiO2@CuGaS2/N719 has a power conversion efficiency of7.4%, which is 23% higher than that of monosensitized dye solar cell. Anchoring CuGaS2 QDs on semiconductor nanoparticles to form QDs/dye co-sensitized solar cells is a promising and feasible approach to enhance light absorption,charge carrier generation as well as to facilitate electron injection comparing to conventional mono-dye sensitized solar cells.
