纱线条干均匀性序列图像测量方法

为了更精确、连续地评价纱线的外观条干均匀性,提出一种基于序列图像的纱线条干均匀性测量方法。通过图像采集系统获取连续的纱线序列图像;根据模糊C-均值（FCM）聚类算法将图像进行阈值分割,得到纱线条干的二值图像;设定阈值去除图像中的孤立点、毛刺点,获得清晰的纱线条干图像,并计算图像中每行纱线直径。 为验证方法的准确性,对７ 种线密度的紧密纺纯棉纱进行了条干测试,并将结果与USTER® Tester 5-S800 条干测试仪的测试结果进行了对比。结果表明：序列图像方法测得的纱线条干均匀性与USTER 条干仪的测试结果高度正相关,证明本文的方法是准确可行的。     

基于亚像素边缘检测的纱线条干均匀度测量

为了精确地评价纱线的表观条干均匀性,提出一种基于亚像素边缘检测的纱线条干均匀度检测方法。首先通过图像采集装置获取纱线图像;然后对纱线图像进行亚像素边缘检测获取纱线边缘点集;利用开运算对获取的边缘点集进行处理,进而获得纱线条干的边缘;最后采用坐标直方图方法计算纱线平均直径和条干CV值。为验证方法的有效性和准确性,对多种不同线密度的纯棉纱线进行测试,并将测试结果与电容式条干仪的均匀度检测及基于模糊C均值分类和Otsu图像法的检测结果进行了对比。结果表明:基于亚像素边缘检测的纱线条干均匀度检测方法与电容式的测量结果有着较好的一致性,证明所提方法可得到准确的结果。     

基于数字图像处理的纱线条干均匀度检测初探

本文以四种不同规格的纯棉纱线为例,提出一种基于数字图像处理技术来检测纱线条干不匀率的方法。采用MRS-4800M48U型扫描仪采集纱线图像,然后对纱线图像进行维纳滤波、阈值分割、形态学开运算处理,得到条干清晰、无噪声的纱线图像,最后基于经处理后的图像计算纱线的直径和纱线的条干CV值,图像法检测出的纱线条干CV值与乌斯特条干仪检测出的结果非常接近,这表明,本文提出的纱线条干均匀度检测方法是可行的,能准确高效地检测出的纱线条干CV值,客观地反映纱线的外观质量。     

应用纱线序列图像的色纺机织物仿真

探讨应用纱线序列图像进行色纺机织物仿真的方法和效果。利用纱线图像采集设备获取5种色纺纱序列图像,然后采用灰度变换、图像阈值分割、形态学运算等图像处理技术获取纱线主体彩色图像。通过对横截面、长度以及弯曲三个参数的调整,建立织物结构模型,将获得的色纺纱主体真实颜色信息填充到模型中,最后根据建立的织物组织变化模型,实现了5种色纺纱平纹、一上三下左斜纹以及二上二下方平织物的外观仿真。认为:该织物仿真方法能够将纤维颜色在织物中的分布效果快速且准确地反映出来,品种适应性较好。     

基于图像分析技术的纱线黑板条干检测

探讨一种基于数字图像处理技术检测纱线条干不匀率方法的应用效果。利用扫描仪采集了9种不同规格的纱线图像,纱线图像经过倾斜校正、自适应中值滤波、阈值分割、形态学开运算处理等,得到条干清晰、无噪声的纱线图像,基于处理后的图像计算纱线直径和纱线条干不匀率。结果表明:图像法检测的纱线条干不匀率与乌斯特条干仪检测的结果非常接近。认为:所提出的纱线条干不匀率检测方法是可行的,能准确、高效地检测出纱线的条干不匀率,客观反映纱线的外观质量。     

一种改进的织物外观真实感模拟高效算法

为提高织物外观真实感模拟算法的效率,提出一种改进的、简洁高效的织物外观模拟算法。在织物外观仿真中,通过优化纱线模型,并利用计算机图形学中的多边形深度缓存算法,结合织物中纱线的反射特性,以及浮长线对织物外观的影响,建立了基于浮长线的屈曲模型,最后结合图像技术,使模拟的织物具有较强的真实感。实验结果表明,这种算法利用二维图像方法达到三维模拟的目的,降低了运算复杂度,提高了效率。     

基于平面镜成像的纱线条干三维合成校准方法

针对二维图像纱线条干均匀度检测存在信息缺失、纱线条干三维合成准确度不高等问题,在平面镜成像的三维检测系统基础上提出一种纱线条干三维合成校准方法。选用4种不同粗细的纯棉集聚纺纱线,用相机在一幅图像中采集各个纱线的多视角图像,分别用校准方法对xoz平面和xoy平面校准,再进行二值化、形态学开运算处理,得到清晰的纱线条干二值图像,根据平面镜成像系统几何关系合成纱线条干三维模型,计算纱线条干各截面上像素点个数及其变异系数,与Uster TESTER 5测得的二维直径及纱线二维直径CV值对比评价纱线条干建模精度。结果表明,三维模型纱线各截面像素点个数与二维直径相关系数在0.987以上,条干均匀度CV值与Uster法结果的极差在2.36%以内,证明校准方法可行。     

应用显著性算法的纱线条干均匀度检测

针对运用图像方法进行纱线条干均匀度检测时,背景黑板、纱线毛羽以及图像噪声等对检测结果影响较大的问题,借鉴人的视觉感知机制,提出一种应用显著性算法检测纱线条干均匀度的方法。对采集到的纱线图像提取颜色和亮度特征,进行显著性分析,突出纱线条干区域,然后利用迭代阈值分割算法和区域滤波,得到准确清晰的纱线条干二值图像,基于此进行直径计算、均匀度分析和纱线疵点判定。通过边缘准确性评价可知,采用所提方法分割得到的纱线条干二值图像有着较高的分割精度。通过与Uster Classimat 5的均匀度检测结果进行比较,证明这种方法可得到准确的结果,与Used Classimat 5 的测量结果有着较好的一致性。     

纤维尺度下数码纱仿真方法

为解决因配色复杂多变,数码纱外观难以直观预测的问题,提出基于纤维单元的模拟方法,用于实现数码纱外观的仿真。依据纤维原料颜色数值,构建纤维级别的纹理模型;根据纺纱工艺参数计算数码纱上的区域色块参数,构建色块排列模型;利用不同组分纤维间渐变规律,同时结合光照模型仿真亮度信息构建颜色渐变模型;采集真实数码纱的直径数据,仿真纱线的直径形态。实验中分别保持颜色和组分不变,模拟出不同组分和颜色的数码纱。结果证明所提出的纱线仿真方法可较快地模拟出数码纱的外观,并且与实际数码纱的外观视觉十分接近,为数码纱的设计开发以及织物仿真奠定了基础。     

基于纱线设计的织物外观仿真方法的研究

织物外观模拟方法是织物CAD系统开发的一项重要研究内容。为了提高织物外观的仿真模拟效果,提出了一种基于纱线设计的织物外观仿真方法,采用意匠格填充进行纱线的设计,并建立起相应的数学模型;还对纱线排列中的算法进行了分析。最后通过对模拟好的纱线按照密度和织物组织进行平铺,来模拟织物的外观。     

Computer simulation of plain woven fabric appearance from yarn photographs

This article proposes a method for simulating plain woven fabric appearance based on photographs taken by still camera of actual yarns along their lengths. The survey mathematically models the transformation of yarns from a straight circular cylinder to a flattened and crimped form in the fabric structure. The simulation is performed by yarn images that are obtained by image processing techniques and resized according to mathematical models developed by means of the software prepared. Transforming circular yarn cross-section to elliptical one for simulating yarn flattening and modelling the crimped shape of yarn by an elastica curve are both convenient and realistic. The simulation of plain woven fabric can be performed by a method based on raster graphics. This article provides a model for yarn shape in fabric structure as well as a method for simulating plain woven fabric appearance. This method may be used in textile industry for design and quality control.     

Mathematical model to predict vertical wicking behaviour. Part II: flow through woven fabric

The aim of the paper is to develop a mathematical model to predict vertical wicking behaviour of woven fabric. The first part of this series (Part I) has dealt with the mathematical model for predicting vertical wicking through yarn. In this part a model has been proposed to predict vertical wicking of the woven fabric, based on the developed yarn model. In order to model the flow through woven fabric along with the vertical flow through liquid carrying threads, the horizontal flow through transverse threads has also been taken into account. A simplified fabric geometrical concept (inclined tube geometry) and Peirce geometry for plain woven fabric have been used to define the fabric structure. Warp and weft linear density, fabric sett and yarn crimp have been considered in the fabric modelling. The theoretical wicking values of the yarn and fabric made from that yarn have been compared. Experimental verification of the model has been carried out using polyester and polypropylene fabrics. The model is found to predict the wicking height with time through the yarns and fabrics with reasonable accuracy.     

采用色纺纱图像的真实感色织物模拟

为解决色织物产品设计周期长,试织打样耗时费力的问题,提出一种采用色纺纱图像的真实感色织物的模拟方法。首先采集彩色纱线图像,运用阈值分割、形态学处理得到纱线主体,获取纱线主体的上、下边界和中心线,进而得到原始纱线图像的主体部分;接着根据椭圆模型和正弦曲线模型对纱线主体图像进行处理,得到纱线在二维织物表面中的形态;最后根据色纱循环和织物组织变换模型来改变经纬纱的覆盖关系,实现了真实感条纹型和格子型色织物的模拟。模拟结果表明：本文算法能够模拟不同种类色织物的织造过程,真实地反映织物的外观效果,且能够调整织物组织和色纱循环参数,提高了现有模拟算法的真实性和适应性。     

Effect of structural parameters of porous yarns and fabric on air permeability and moisture transfer of double-face woven fabrics

In this study, effect of fabric structural parameters of double-face woven fabrics including kind of porous yarn namely micro-porous yarn and hollow yarn, hole size of hollow yarn, percentage of these yarns in double-face woven fabric structure, and finally weft density on air permeability and moisture transfer of woven fabrics was evaluated. These yarns were produced by using water-soluble continuous polyvinyl alcohol filaments as core part for hollow yarns and as doubling yarn in micro-porous yarn. Results revealed the effect of kind of porous yarn, hole size of hollow yarn, and weft density on air permeability and moisture transfer of woven fabrics. The percentage of porous yarns as weft did not show obvious trend. Analysis of variance was used to study the effect of these variables on air permeability and moisture transfer of double-face woven fabrics statistically.     

基于数字单元法的三维正交织物微观几何结构建模

为了反映织物内部纱线的空间构型和微观几何结构,针对在织物建模过程中,因忽略纤维间的相互作用而引起的纱线截面形状变化的问题,基于数字单元法理论,提出了一种计算纤维间摩擦力的方法。通过纱线纤维化离散,用数值模拟和仿真方法模拟三维正交织物成型过程,建立了5种精度递进的微观几何结构数值模型。5种模型中的每根纱线分别由4、7、12、19和37根数字纤维表征。研究结果表明:随着纱线纤维化离散程度的提高,仿真时间延长,织物厚度减小,纤维体积分数增大,节点平均作用力下降速度变缓,势能变小;当每根纱线由19根数字纤维组成时,所建织物的微观几何结构数值模型与真实织物样本在显微镜下的内部切片图像较为吻合。     

Ring frame process parameters and fabric comfort. Part I – low-stress mechanical properties of fabrics

Influence of ring frame process parameters, namely twist multiplier of yarn, spindle speed and ring frame draft, on some of the yarn characteristics has been studied. The low-stress mechanical characteristics of woven and knitted fabrics made out of these yarns have also been reported in the present paper. Yarn packing factor, which is directly related with the yarn diameter, has direct impact on fabric comfort related characteristics. All the studied ring frame process parameters, i.e. yarn twist, ring frame draft and spindle speed, have inverse effect on the yarn diameter, which means the yarn diameter reduces with the increase in one of the process parameters by keeping the other two parameters constant. The impact of draft on reduction in yarn diameter is found to be higher as compare to other two parameters. All these ring frame process parameters have significant impact on other yarn parameters also. The increase in yarn twist, spindle speed and draft result in increase in flexural rigidity, unevenness and imperfections of yarn and decrease in yarn hairiness. All the low-stress mechanical properties, i.e. tensile, shear, bending, compression and surface, of both woven and knitted are affected by the above ring frame parameters. The thickness of fabrics changes with the yarn compactness, i.e. with the reduction in yarn diameter. The study revealed that by changing the above ring frame process parameters, it is possible to manipulate the fabric handle characteristics without changing the fabric constructional parameters.     

基于芳纶平纹织物微观几何结构的纱线抽拔力学性能分析

为研究芳纶平纹织物纱线抽拔力学性能及各参数的影响规律,建立纱线抽拔数学模型,为后续数值模型提供理论基础.采用数字单元法模拟芳纶平纹织物织造过程,获得其微观几何模型,并计算得出纱线轮廓.在此基础上,使用ABAQUS模拟单纱抽拔过程,建立纱线厚度方向单层网格划分准则和纱线材料属性,获得横向预紧力、纱线间摩擦因数对纱线抽拔力...     

应用混色纱纹理信息的纬编针织物模拟

为研究数码混色纱纬编针织物的外观色彩及纹影的模拟方法,利用图像处理技术对采集的图像进行平滑去噪,得到剔除细节的模糊图像,在Lab 空间下运用彩色图像硬聚类算法对平滑后的图像进行聚类分割,得到混色纱主体图像,获取其左右的边界和中心线信息;然后在经典的Pierce 线圈模型的基础上,利用混色纱主体图像的廓线信息完成由纱线到线圈圈弧和圈柱的映射;最终根据不同组织的圈弧和圈柱的覆盖关系,得到基本纬编针织物组织。结果表明,提出的纱线映射线圈算法,通过织物组织结构及密度可模拟混色纱纬编织物的混色色彩及外观纹影。