织物疵点检测中自适应正交小波基的构造

提出了一种用于织物疵点检测的自适应正交小波基的构造方法.该方法从小波滤波器系数满足的正交归一化条件入手,采用一定数量参数角的正弦和余弦函数构造出一定长度的正交小波滤波器系数的统一解析式;以分解子图中像素最大能量值最小作为逼近条件,采用遗传算法作为寻优算法,从而实现针对不同的织物,自适应地构造小波基.同时,实验证明了自适应小波基的对疵点图像分解效果.     

基于计算机视觉的织物疵点自动检测

用小波变换结合BP神经网络对织物疵点进行检测和分类.采用平纹坯布作为试样,对油渍、缺经、缺纬疵点进行识别.摄相机摄取256×256图像,将拾取图像进行小波分解,然后把小波分解后的图像灰度值作为特征参数输入到BP神经网络进行检测识别.实验结果表明,用这种方法识别织物疵点,识别率可达到98%.     

基于自适应双正交小波的织物疵点边缘检测

针对织物疵点边缘检测问题,分析了"最佳"边缘检测滤波器设计的准则,以及构造自适应双正交小波的优化目标函数,提出了一种基于自适应双正交小波的图像边缘检测方法.实验结果表明,与已有的基于小波的图像边缘检测方法相比,本方法具有更好的边缘检测能力和鲁棒性.     

用于疵点检测的织物自适应正交小波的实现

应用随机算法并给以一定的约束条件，可以有效地由满足正交归一条件的滤波器中，优化获得与织物纹理相匹配的滤波器。应用这种织物自适应滤波器对织物灰度图像进行小波分解，就可使分解后的子图像能很好地分别包含织物的纬向和经向纹理信息，从而可有效地应用于织物疵点的自动检测。     

基于小波变换和最大熵的织物疵点检测

首先选取最优小波基对织物疵点图像进行分解,并对分解后的水平及垂直高频系数进行灰度值归一化,然后分别求出水平和垂直细节图像的最大熵及平均熵,通过比较判断出疵点类型,最后对平均熵大的细节图像进行最大熵原理的分割,得到最终的疵点检测结果。仿真实验表明该方法对常见纬向和径向类织物疵点的检测是有效的。     

基于小波变换的织物疵点检测

本文基于小波变换原理进行织物疵点检测。使用DH-SV 1410FM数字相机采集平纹坯布图样,应用中值滤波和Laplacian算子对图像做去噪和锐化处理。采用Mallat算法对预处理后的图像进行小波分解,分别提取经纬子图的能量、方差、熵、逆差距和极差等特征值,并对提取的特征值进行归一化处理。实验结果表明,疵点使织物图像在经纬方向上产生了不规则的纹理走向,不同类疵点图像的特征值归一化曲线在疵点处有明显的变化。该研究对判断织物是否有疵点的存在、判断疵点的大致走向和确定疵点的位置具有一定的参考价值。     

基于连续小波变换的非结构化畸变织物疵点自动检测

采用连续小波变换对非结构化畸变疵点进行自动检测．介绍了具有代表性的连续小波——墨西哥草帽小波基本原理及其对疵点的边缘增强效应；设计疵点自适应小波，确定最佳的小波参数；并将其应用于织物疵点的自动检测；通过对两种非结构化畸变织物疵点的实际检测来验证该方法的可行性．实验表明，该方法的检测速度最高可达6．5m／min．     

基于二维连续小波变换的织物疵点检测

同正常织物纹理比较,疵点区域由于其纹理不规则及变形而导致不同的局部纹理特征。利用二维连续小波特征,能在时域和频域上对织物图像同时实现任意尺度和旋转角度的变换。通过纹理模型和频谱分析,确定出最优的变换尺度和旋转角度,并由预先确定的全局阈值从小波变换系数的模中进行疵点的分割。实际疵点的检测结果表明该方法是可行的。     

基于Labview的针织物疵点检测

介绍一种基于Labview的针织物疵点检测系统与方法.其采用Labview软件并结合Matlab编程,首先对采集的针织物图像进行中值滤波和二值化处理,接着采用db小波分解图像,最后对分解后的经向和纬向纹理子图像分别提取特征值,由此检测和识别疵点.实验结果表明此方法可以有效地检测平针、罗纹和双罗纹针织物的常见疵点.     

基于自适应正交小波的机织物密度自动检测的研究

为了将计算机视觉应用于织物经纬密自动检测，提出了建立机织物自适应小波分解滤波器并研究了织物密度自动检测的方法。应用织物自适应滤波器对织物灰度图像进行小波分解，就可使分解后的子图像能很好地分别包含织物的纬向和经向纹理信息，从而可将织物子图像二值化后，根据其黑白交替变化规律，计算出织物的经纬纱密度。实验结果证明自动检测和人工测量相比，误差在3％以内。     

A Novel One-Dimensional Projection Based Method for Fabric Texture Representation

Automated defect detection in woven fabrics for quality control is still a challenging novelty detection problem,while the efficient representation of fabric texture is essential for it.This paper presents a novel method for fabric texture representation.Benefiting from the characteristics of the weaving process,the major texture information of woven fabric is concentrated in the warp and weft directions.Thus,the proposed method is firstly to project the image patch along warp and weft directions to obtain projected vectors containing warp and weft informations.Secondly,the obtained vectors instead of image patch,are used to extract the features that are able to represent fabric texture.Finally,the t-test is applied to verifying the usefulness of the proposed method in discriminating defective and normal fabric textures.The experiments on various defective samples demonstrate that the method yields a robust and good performance in representing fabric texture and discriminating defects.     

Fabric Defect Detection Using Adaptive Wavelet Transform

A method of woven fabric defect detection using the wavelet transform adaptive to the fabric has been developed. With reference to the orthogonality constrains of Daubechies wavelet, by taking the minimization of the energy or the gray level of the pixels hi the output sub-images as the additional conditions and using the random algorithm method, two sets of wavelet filters adapted to the fabric texture were formed. The original images of normal fabric texture and the fabric texture with defects were decomposed into horizontal and vertical sub-images by using these filters and the feature indices of these sub-images were also extracted. By comparing the feature indices of the normal texture with that of the defective texture, the fabric defects can be successfully detected and located.     

打纬及开关车织物横档疵点

以实验的方法解释了织机在未采用张力补偿措施前提下,产生开关车织物横档疵点的原因。织机开关车时由于主轴转速、钢筘打纬速度达不到正常数值,使经纱张力及钢筘打纬力达不到一定的正常数值,以致打纬过程中经纬纱线相对滑移量比织机正常运转时的数值小、共同移动量比正常运转时的数值大,所形成的织物达不到正常的纬密,在织物上产生横档疵点。同时,也指出了长期以来对织物横档疵点成因一种肤浅的解释。     

多层机织物增强结构的设计

纺织结构在纤维增强复合材料的成型中占有越来越重要的地位．增强纤维加工成纺织结构可以方便复合材料的加工,提高复合材料的韧性和损伤容限,使材料不宜分层．本文主要介绍了各层经纬密度不同的多层机织物的设计方法     

Relationship between Beating and Setting-on Place

In this paper,what causes the setting-on place of woven fabrics without adopting tension compensation is explained by means of experimental methods.Owing to that the main shaft speed and the beating speed of reed can not attain the normal values at setting-on,the warp tension and the beating force of the reed can neither reach the normal level.Therefore,the relative slippage movement of the weft against the warp during beating will be less,while the common movement of the weft together with the warp will be bigger than those at nor-mal running.As a result,the setting-on place is then     

基于摄像头采集和图像处理的机织物密度检测

采用CCD摄像头拍摄机织物图像,根据其特性进行图像处理,自动寻找条纹方向并旋转图像.通过运用误差处理的方法,得到精确的织物经纬密度.研究结果表明,拍摄一幅图像即可快速得到织物的经纬两个方向的密度,比傅里叶变换和小波变换计算量小,并可以用于实际生产过程中的纺织品密度在线检测.     

织物的膜理论

为了对织物膜结构和服装进行虚拟模拟，例如膜结构的张紧和褶皱以及服装的悬垂和屈曲，建立了编织物的膜理论．编织物的细观编织结构被引入了膜理论，织物的经线和纬线被选为曲线坐标轴，未变形的纱线作为Lagrangian坐标轴，变了形的纱线作为Eulerian坐标轴．在变形中考虑经线和纱线之间夹角．该理论被用于织物膜的张紧分析．数值结果表明，当应变e12达0．06时，由于纱线夹角的改变导致的应力增加占总应力的25％左右．     

Theoretical Calculation Model of Single Rip Tearing Strength for the Nonwoven Composites

The nonwoven composites have sandwich structure, with the first and third layers being nonwovens and the middle layer of woven fabric. On the basis of tests of the single rip tearing strength and drawing out resistances of both the nonwoven composites and the woven fabric, the single rip tearing failure mechanism of the composites were analyzed. Then theoretical calculation model for the single rip tearing strength was established, which indicates that the breaking strength of warp and weft yams in the nonwoven composites, the density of warp and weft yarns and drawing out resistances are the main influencing factors. In the end, experimental verification was made, which shows that theoretical values conform to the measured values well.     

织编物的组织结构

织编物是把机织与针织的原理相结合所生产出的一种带条纹的织物。为了深入研究织编物的特性、用以指导在设计这一类织编物时所遇到的种种问题,我们有必要对织编物的组织结构进行研究。本文就织编物的厚度与经纬纱的细度,经纬纱的密度与用纱量之间的关系,织编物的几种基本组织结构及其经纬密度的配置,以及经纬向的强力与伸长,纱线复盖度与透光及透气性的问题一一作了研究,虽然这一工作仅仅是开始,但它有助于对这类新型织物的生产研究工作,以供这方面工作的同志参考。