A computer vision-based system for automatic detection of misarranged warp yarns in yarn-dyed fabric. Part I: continuous segmentation of warp yarns

In textile and garment industries, misarranged warp yarns of yarn-dyed fabrics disorganize the layout of fabrics and lead to poor product quality. This series of studies aims to develop a computer vision-based system for automatic detection of misarranged color warp yarns in terms of high efficiency and good accuracy. Four main parts are included in this series of studies: warp yarn segmentation, fabric image stitching, warp regional segmentation, and yarn layout proofing. This paper proposes a continuous segmentation method of warp yarns to detect the misarranged color warp yarns for yarn-dyed fabrics automatically, which is the foundation of the developed computer vision-based system. The proposed framework consists of two main components: warp yarn segmentation and fabric image stitching. Firstly, the sequence images of a fabric stripe are captured using a designed offline image acquisition platform. Secondly, the warp yarns in the sequence images are segmented by a sub-image projection-based method successively. Thirdly, the sequence images are stitched by a yarn-template matching method based on their warp segmentation results. Finally, the continuous segmentation result of warp yarns is saved for the further processing of warp regional segmentation and color warp layout proofing. The proposed method has been evaluated on 720 fabric images of five fabric examples with plain and 2/2 twill, and experimental results show that the proposed method can realize the continuous segmentation of warp yarns in yarn-dyed fabrics with the yarn segmentation accuracy of 97.43% and image stitching accuracy of 99.53%.     

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。     

Automatic inspection of yarn-dyed fabric density by mathematical statistics of sub-images

To inspect the yarn-dyed fabric density automatically, an effective image analysis method based on mathematical statistics of sub-images is proposed in this paper. This method consists of two main steps: rough measurement and precise measurement. The rough measurement is based on projection curve of the whole fabric image. The fabric image is converted into HSV model from RGB model firstly, and then the projection curve of value is gained directly. The number of yarns is obtained by counting the number of peaks in the curve roughly. The precise measurement is based on projection curves of the fabric sub-images. According to the roughly estimated yarn number, the whole fabric image is divided into a certain amount of sub-images and the projection method is applied to all the sub-images, respectively. The probability distribution map of peaks is obtained by processing the projection curves of all sub-images and the positions of the yarn center are located in the frequency curve generated from the map by mathematical statistics method. The number of peaks in the frequency curve is counted, and, therefore, the number of yarns is detected, and the density can be calculated precisely. The experimental results proved that the proposed method is effective for yarn-dyed fabrics and can satisfy the requirement for production practice.     

纯棉色织提花织物的染整工艺实践

纯棉提花织物主要采用色织工艺生产，织物以平纹为主，提花部分具有较长的浮长线；织物要求花形饱满、圆润，手感柔软、悬垂性好，耐磨。对此染色工艺要求达到织物色牢度好，并尽量采用环保型染料；后整理过程则要注意满足织物的手感要求，避免长浮线被勾挂，同时要使织物经向少受张力，避免花纹被拉平。     

氨纶弹力织物的开发和生产

文章对色织氨纶弹力织物的染纱、织造、后整理的生产工艺作了较详尽的阐述，并列出多种色织和白织氨纶弹力织物规格以供参考。     

基于MATLAB图像处理的织物纱线直径测量

针对织物中纱线细度的测量,先用切片技术制作织物切片获得其切片图,再用MATLAB图形处理函数对其进行处理以利于测量,然后使用CU-2纤维细度仪中的显微图像分析应用软件包测量出纱线直径,并与直接测量从织物中拆下的纱线直径进行了比较。结果表明通过MATLAB图像处理纱线切片的方法所测得的纱线直径准确可靠。     

色织CAD系统的开发

介绍了Windows XP界面下的色织CAD系统，包括组织图设计、纱线设计和织物外观模拟。该软件采用Visual Basic 6．0在Windows XP环境下开发。     

棉氨弹性纱线及其在色织弹力绉设计中的运用

论述了棉氨弹性纱线的主要特征，并在弹力绉面料的设计中就如何应用氨纶包芯（覆）纱线，对织物的规格、组织、配色、绉纹造型设计等方面的问题作了分析探讨。     

Genetic algorithm‐based detection of the layout of color yarns

In this paper a novel method based on a genetic algorithm is proposed to recognize the layout of color yarns of yarn‐dyed fabric from the color pattern. The principle of a genetic algorithm is described first, and then the theories of roulette wheel selection method, crossover operation, and mutation operation are explained with the practical problem. Elitist selection is used to search for the correct result of the layout of color yarns. Some new chromosomes are added to the new generation in the genetic algorithm to avoid the local optimization. The repeat element of the layout of color yarns is then detected with period extraction. The repeat element of color pattern with the layout of color yarns is output together. Experiments on some color patterns recognized from actual yarn‐dyed fabrics, some color patterns simulated manually, and some color patterns including error color information of floats prove that the method proposed in this paper is effective for detecting the layout of color yarns from the color pattern of yarn‐dyed fabric, and it has a fault‐tolerance ability to some degree.     

亚麻增强聚丙烯复合材料薄板的冲击性能

以亚麻纤维为增强体,与聚丙烯(PP)树脂长丝进行丝束级混合,形成PP包覆亚麻的纱线结构,利用机织工艺织成二维机织布,作为复合材料的预制件。采用层合热压的方法制备亚麻/PP复合材料薄板。通过对板材冲击性能的测试以及破坏形貌的分析,研究了亚麻/PP薄板的冲击破坏机制以及影响板材冲击性能的因素。结果表明:斜纹组织板材的冲击性能优于相同制备工艺的平纹组织板材;树脂、纤维、铺层数、冲击速度等因素对板材的冲击性能均有影响。     

A computer vision-based system for automatic detection of misarranged warp yarns in yarn-dyed fabric. Part II: warp region segmentation

This series of studies aim to develop a computer vision-based system for automatic detection of misarranged color warp yarns to replace manpower and improve efficiency. Based on the warp yarn segmentation and fabric image stitching methods presented in Part I, this paper proposes a stepwise segmentation method of warp regions, as a core of the developed computer vision-based system, to detect the layout of color yarns for yarn-dyed fabrics automatically. The proposed framework consists of two main components: rough warp region segmentation and precise warp region merging which are realized by analyzing correlation coefficient of color histograms among segmented warp yarns and warp regions successively. The proposed method has been evaluated on 543 fabric images of four fabric samples consisting of 5533 warp regions, and experimental results show that the proposed method can realize the warp region segmentation in yarn dyed fabrics with the average accuracy of 99.47%.     

Geometry of plain weave fabric under shear deformation. Part I: measurement of exterior positions of yarns

Behaviour of woven fabrics in all directions is important in some fabric applications. Dealing with geometrical deformation of fabric under shear stress is the main attempt of this paper. A method for detecting exterior positions of yarns in fabric, namely variation in warp-weft yarns angle and sett of yarns is developed in the present part. For this purpose, the fast Fourier transform (FFT) method is modified for detecting exterior position of yarns in sheared fabric. In an empirical work, two kinds of plain weave fabrics, cotton and polypropylene, are considered and specimens are prepared in different dimensions with identical aspect ration. Exterior positions of yarns in certain elongations are computed by proposed method for each specimen. It was found that the modified FFT technique is valid for evaluating exterior positions of yarns in sheared fabric. Moreover, it is observed that there is a critical state in behaviour of woven fabric under shear deformation. In subsequent parts, the treatment of fabric under shear deformation will be simulated and compared with results of present part.     

雪尼尔牛仔布的开发

雪尼尔线是一种由芯线和断丝绒纤维构成的花式纱线,一般用于家纺产品上.介绍了利用雪尼尔纱线开发牛仔布的思路、生产工艺和技术措施.为获得牛仔布产品的更好外观和服用性能,适应市场对面料的需求,开发出的雪尼尔牛仔布产品风格独特,赢得了市场的欢迎.     

基于Hough变换的机织物组织点自动定位

为实现机织物的组织识别,先要完成组织点的定位和识别。为克服传统的组织点分割方法的局限性,提出采用Hough变换检测织物图像中的经纱和纬纱的倾斜角度,然后对织物图像中的像素点进行坐标变换。在变换后的图像中对像素点进行按行按列灰度累加,通过确定累加曲线中的谷点即可完成织物的经纬纱分割。对经纱和纬纱分割结果进行合并,可得到机织物组织点分割结果。实验结果表明,所提出的算法对存在纱线倾斜的不同织物均可实现组织点的成功定位。     

Length of the yarn in plain‐weave crimp wave

Yarn axis geometry in plain‐weave fabrics has been described by different models. Yet, they do not capture its exact shape, because (1) the geometry of each crimp wave in a fabric is unique to that fabric and as such it differs from any generalized model, and (2) the length of the yarn axis, an important parameter, is more influenced by the height of the crimp wave than by any arbitrary definition of its shape. Crimp of the warp/weft is defined as the ratio of the length of the yarn axis in one wave and its wave length; the latter is the spacing (pitch) of the neighboring weft/warp yarns. Crimp can be calculated in accordance with the crimp wave shape definition, which differs from reality. In this paper, a new and very simple method of calculating the yarn crimp is proposed and validated through experimental measurements. The results provide an instrument for easy calculation of yarn lengths when crimp wave amplitudes and wavelengths are known.     

Effect of Weave Parameters on the Tear Strength of Woven Fabrics

ABSTRACT

The fabric tear strength is an important parameter in textile material, ever since it is close to relate to the service of the fabric. Tear strength of the fabrics depends on the flexibility of the yarn in fabric structure. In this research, the tear strength of 11 cotton woven fabrics is analyzed based on the weave parameters such as crossing over firmness factor (CFF), Floating Yarn Factor (FYF), Fabric Firmness Factor (FFF) and weave factor (P1).     

碳纤维二维编织管状织物的编织工艺

针对碳纤维在二维编织过程中不耐扭折、易受损断纱的问题,通过拉伸性能实验和导纱瓷眼折角磨损实验分析了碳纤维复丝的可编织性能,探讨了纱管在缠绕过程中应注意的问题。在24 锭二维编织机上编织了8 种不同工艺参数的碳纤维管状编织物,研究了编织工艺对织物外观起毛情况及力学性能的影响。结果表明：碳纤维复丝的断裂强度为86.39 cN/tex,断裂伸长率为1.12%,断裂强度远高于其他纤维,但延伸性差;影响碳纤维复丝在导纱瓷眼处折角磨损程度的因素依次为牵引力、折角、编织速度;在编织纱线根数不变的情况下,随编织节距的减小,管状编织物的面密度逐渐增加,起毛现象严重,编织物的拉伸断裂强力降低。     

碳黑导电纤维的导电性能

为开发和拓展碳黑导电纤维的应用,利用体式显微镜和扫描电子显微镜对导电纤维的表面形态进行表征,测试了不同碳黑含量、不同线密度的导电纱线在标准环境下的电阻大小,并线性拟合了导电纱线电阻大小与测量长度的关系,对比分析了热定型温度和洗涤次数对纱线导电性能的影响。结果表明：碳黑导电成分在纤维表面,改善了锦纶纤维的力学性能;碳含量较高的纤维其导电性能优于碳含量较低的纤维,导电纱线电阻与它们的长度成正比,与截面成反比;锦纶导电纱的电阻值随着温度的升高而减小,纱线热处理温度不超过120 ℃;洗涤次数对锦纶导电纱线的导电性能影响小,纱线导电性能稳定。     

A study on siro-, solo-, compact-, and conventional ring-spun yarns. Part I: structural and migratory properties of the yarns

Properties of spun yarns are mainly affected by fiber properties and yarn structure. Yarn structure is principally influenced by the spinning system. In fact, each spinning system tends to produce a distinctive yarn structure. Recent refinements in spinning technologies have yielded significant improvement in yarn structure. Siro, solo and compact spinning are the new spinning systems to have made a breakthrough until recently. Of the various structural parameters for staple yarns, fiber migration has a crucial influence on the yarn mechanical properties. Thus, the need for precise and concise information about fiber migration becomes important for better understanding of yarn structure and hence yarn mechanical behavior. The work presented here aims to analyze fiber migration in siro-, solo-, compact-, and conventional ring-spun yarns by varying the twist factor. The results demonstrate that the siro-spun yarns exhibit the highest fiber migration parameters, followed by compact-spun yarns, solo-spun yarns, and conventional ring-spun yarns.     

Peirce平纹机织物结构模型的计算精确度

为提出一种可估计任意机织物结构理论模型精度的思路,利用Peirce织物结构理论计算平纹织物纱线的几何形态。用Keyence数码显微镜非破坏性地实际测量织物的关键点位置,并利用保形3次B样条曲线模拟织物结构。采用离散Fréchet距离进行判别理论计算的纱线构形曲线和实测模拟的纱线构形曲线的相似性程度。计算两条曲线上对应波峰点、波谷点及相邻波峰点与波谷点的离散Fréchet距离差的绝对值,得到一个可认为曲线相似时的阈值 ,并与织物厚度相比较,提出纱线中心线形状相似度的概念。阈值 越小,则相似度越高,织物结构模型计算的精确度越高。通过MatLab应用程序,对两种平纹组织三维重建织物结构模型的相似性进行了分析并计算出样品1和样品2经、纬纱的相似度值分别为90%,86%,82%,94%。