Parameterization of Seersucker Woven Fabrics Using Laser Techniques

AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX

PARAMETERIZATION OF SEERSUCKER WOVEN FABRICS USING LASER TECHNIQUES

Łukasz Frącczak1, Domagała Rafał1, Zgórniak Piotr1, Małgorzata Matusiak2

1Faculty of Mechanical Engineering, Institute of Machine Tools and Production Engineering, Lodz University of Technology, Lodz, Poland 2Faculty of Material Technologies and Textile Design, Institute of Architecture of Textiles, Lodz University of Technology, Lodz, Poland

Abstract:

Seersucker woven fabrics are increasingly used in the textile industry. Unfortunately, their popularity is limited due to the lack of standards and parameterization of their structure. Thus, the designer of the finished product (clothing, bedding, or decorative items) has problems with ordering a fabric with a specific structure and properties. In this context, it is necessary to parameterize them. This paper presents a method for measuring the surface geometry of seersucker woven fabrics using laser techniques. The surface geometry of the seersucker woven fabric was determined using adapted roughness parameters, such as Wz, Ra, and Rz, as well as by using a hypsometric map.

Keywords:

seersucker woven fabrics, surface geometry, laser scanning, parameterization

1. Introduction Seersucker woven fabrics are increasingly used in different applications. They are applied as decorative fabrics, but Nowadays, the technology of 3D fabrics is developing increasingly often, they are used in the clothing industry. In dynamically. Three-dimensional fabrics are defined as fabrics clothing made of seersucker woven fabrics, the geometry of having a third dimension in the form of thickness of the layer [1]. the seersucker effect has a significant influence on perceptible There are different definitions and different classifications of 3D comfort. It is due to the fact that the geometry of the seersucker fabrics. The classification proposed by Khokar [2] is based on effect influences the amount of fabric surface directly adhering the method of the 3D fabrics’ manufacture. It distinguishes five to the human body. In the same way, the geometry of the groups of the 3D woven fabrics manufactured using 2D weaving seersucker effect influences the amount of air between the (four groups) and 3D weaving (one group). Seersucker woven clothing surface and the human skin. It influences further fabrics can be considered as an example of 3D woven fabrics. parameters of clothing, such as air permeability, water vapor Some researchers classify them as 2D+ woven structures. permeability, thermal resistance, and many other factors related There is also an opinion that the structure of the seersucker to comfort. Taking these into consideration, it is very important woven fabrics is 2D, but at the time of weaving, the used to parameterize the geometry of the seersucker fabrics technological parameters facilitate the creation of fabric with correctly, from which it will be possible to analyze precisely the some 3D effect. Due to this fact, the seersucker woven fabric properties of these unconventional fabrics in relation to their cannot be classified as a pure 3D fabric. However, taking into geometrical structure. account the definition of 3D textile structures, the seersucker woven fabrics have a third dimension – thickness – which At present, irregularities in smooth textile surfaces can be cannot be neglected. This type of fabric is increasingly used in measured using contact and noncontact methods [6–11]. One the textile industry. The seersucker fabrics are manufactured of the most popular of the friction- and roughness-measuring using different methods, e.g., using chemical processes, using instruments is the Kawabata Evaluation System for Fabrics yarns with different degrees of elasticity in the weft direction, (KES-FB4) module [6, 9, 11]. This system uses the contact or created as a result of varying yarn tension in the warp [3–5]. method to assess the surface properties of textile materials. Because the seersucker woven fabrics in their puckered parts In the latter case, some parts of the warp threads have are deformed even with a slight touch, the use of this device significantly less tension than the remaining parts of the warp can cause a large measurement error in the results. threads. It causes the length of the worked fabric threads of lower tension to be much higher than the length of warp threads Therefore, it is necessary to use noncontact measurement of higher tension. The excessive length of the less-tensioned methods for assessment of the surface properties of the warp threads causes the puckering of the part of fabric created seersucker woven fabrics. Talysurf CLI-500 is one such by these threads, whereas the part of fabric created by the measuring device [12]. It is a measuring system designed for more-tensioned warp threads has a flat surface. As a result, precise surface measurements. Vik and Vikova [13] applied the puckered and flat strips occur on the fabric surface in the the Talysurf 500 system to measure the topography of 3D warp direction. Such a kind of puckering of the fabric surface is textile printing in the form of Braille symbols. The aim of this called the seersucker effect. work was to make communication between blind people and the world easier through the symbols applied on the apparel http://www.autexrj.com 243 AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX and textile. Among others, the authors stated that in the case of absolute resolution, the Talysurf system was five times worse than the LEXT confocal microscope. Nevertheless, the final resolution of this system was sufficient for the purpose of the investigations. It was also stated that the results from the Talysurf were affected by flexibility and less by reflectance of textiles [13]. Mooneghi et al. [14] analyzed the different methods of evaluating the surface roughness of textile fabrics. On the basis of literature review, they listed the advantages and disadvantages of 17 different methods. Additionally, the authors defined some important parameters characterizing the surface of textile materials, such as woven, knitted, and nonwoven fabrics.

Matusiak and Fracczak [15] used laser scanning to determine Figure 1. Picture of the seersucker fabric analyzed in the experiment. Table 1. Basic structural parameters of the investigated seersucker the surface characteristics of seersucker woven fabrics. They woven fabrics analyzed seersucker fabrics with the seersucker effect in both warp and weft directions. The authors stated that in the case Value of the seersucker woven fabrics, the surface measurement Parameter Unit should contain at least one full repeat of the seersucker effect Sample 1 in the warp direction and one full repeat of weave in the weft Warp I – 20 tex × 2 cotton direction [15]. They elaborated a preliminary proposal of a Warp II – 20 tex × 2 cotton measurement method for assessment of the surface geometry of seersucker woven fabrics using laser scanning [15–17]. In Weft – 20 tex × 2 cotton this method, a laser scanner was used to generate the scanned Weave–warp I – Plain point cloud representing the fabric surface and to transform the point cloud into the fabric surface simulation. In the next step Weave–warp II – Rib 2/2 of the proposed method, straight lines were projected onto the Warp density cm–1 25.2 simulated seersucker surface in the warp and weft directions. In this way, curves reflecting the topography of the seersucker Weft density cm–1 22.9 fabrics were obtained. Then, the curves containing information about the shape of the fabric surface were established in order 2.2. Method used to determine the parameter Wz. This measurement method is affected by errors caused by the successive steps of surface In the new method, the manner of fabric scanning was processing and the generation of the curve showing the outline modified. First, the fabric was spread on a flat table, smoothing of the surface of the seersucker fabric. Another disadvantage of it slightly, and then pressed on the edges with two elements this method is its time consumption, as most of the operations that were positioned along the weft and the warp (Figure 2). are performed manually. Therefore, we decided to improve Then, the ends of the specimen were blocked with magnetic this method by accelerating the parametric assessment of the holders in order to avoid an accidental displacement of the fabric’s geometry. fabric. It should be mentioned here that in the case of the elastic fabrics, the fabrics should be subjected to certain amount of pre-tension. But in the present work, the fabrics 2. Experimental were nonelastic. Their dimensions were stable. Due to this fact, blocking the fabrics’ edges by magnetic holders was sufficient The aim of the presented work was to elaborate a modified to obtain correct results, because the elasticity effect did not method for the assessment of the surface geometry of occur. The fabric prepared in such a way was scanned using a seersucker woven fabrics using 3D laser scanning. The scanning set consisting of the “CimCore Infinity 2” measuring elaborated procedure was applied for determination of the arm with the ScanWorks v4i scanning head. The measurement geometrical parameters of the seersucker woven fabric made was performed under standard laboratory conditions. The of cotton. measuring stand is shown in Figure 2.

2.1. Material The scanning was performed at 30 Hz frequency, and 100% of the points projected onto the surface of the scanned fabric were In order to elaborate the modified method for assessment of the recorded. Optimal scanning parameters were obtained using surface parameters of the seersucker woven fabric, the cotton the “autoexopsure” function. The acquisition of points from the fabric was subjected to a predetermined share of puckered fabric was carried out in a repeated manner, by collecting points strips in the warp direction (Figure 1). twice in two mutually perpendicular directions (in the directions of the warp and the weft). Furthermore, attention was paid to The basic parameters of the seersucker woven fabric applied possible problems related to determining the position of the in the present work are shown in Table 1. fabric on the table and eliminating any discontinuities in the http://www.autexrj.com/ 244 AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX obtained point clouds (by additional scanning of the fabric at outliers” (the function search for the most mismatched points selected locations). in the point cloud). The sensitivity value for these functions was set at 66.67%. Next, the maximum distance between the points The exemplary raw data of the scanned fabric are shown in was estimated, which was 0.18 mm for the selected fabric; the Figure 3a. Then, the scans were processed using the GeoMagic average distance between the points was 0.042 mm and the software. All the scans were combined into one point cloud with standard deviation was 0.03 mm. Based on these data, it was about 7 million points. The surfaces of the positioning elements decided that the threshold to cut off noisy points (this is the and the table were used for creation of planes that were next minimum distance that a given point has from the other points applied to determine the coordinate system associated with at which the point is considered to be not matching with the the scanned fabric. The coordinate system was determined in point cloud) will be 0.05 mm. such a way that the Z-axis coincided with the thickness of the seersucker fabric (puckered elements), the Y-axis coincided In this way, the number of points was reduced to around 2 with the direction of the weft, while the X-axis coincided with the million. It should be emphasized that when comparing point direction of the warp. Then, all points that were not related to clouds from before analysis and after analysis, the noise the fabric were rejected. The effect of this process is shown in between the data points was determined at the level of ± Figure 3b. In further stages of data processing, tools were used 0.05 mm. to eliminate points of high noise and to delete unnecessary points. The point cloud obtained in the described manner was imported into the MATLAB R2017 software, using which the In order to limit the number of points and improve the quality topography of the fabric was analyzed. In order to speed up of the scanned point cloud, the following GeoMagic functions the calculations, the total point cloud was additionally cut to the were used: “select disconnected components” and “select dimensions shown in Figure 4a.

Then, a 50 mm × 50 mm fragment (Figure 4b) was selected from the scanned fabric so that the fabric geometry could be further analyzed. The selection of the fragment was made

Figure 2. Scanning stand for the seersucker fabrics: a) general view; b) Figure 4. Scanned fabric: a) scanning range 80 mm along the weft and scanning process. 200 mm (from 30 to 230 mm) toward the warp; b) selected fragment with side lengths 50 mm × 50 mm.

a) b)

Figure 3. A cloud of scanned fabric points: a) raw data; b) scan of fabric after data processing.

http://www.autexrj.com/ 245 AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX in such a way that in the weft direction, the analyzed fabric Similar analysis was also carried out using the MATLAB sample starts from the beginning of the puckered stripe and, software. However, instead of the generated lines, the point in the warp direction, at the beginning of the full repeat of the cloud obtained from scanning was used to analyze in this seersucker effect (Figure 4a). Determination of the beginning stage of the investigations. From this point cloud, strips with a of the measurement sample in the warp direction is purely width of about 0.1 mm were cut (Figure 5) in such a way that subjective, because in the discussed seersucker fabric, it is the distance between the beginning edges of two consecutive very difficult to determine the beginning point of the wave of strips was 1 mm. Each strip was divided into five measurement the seersucker effect. The puckered places of the fabric along ranges. Then, for each of these strips, the measurement points, the puckered strips are distributed randomly and unevenly namely, the highest and the lowest in a given measurement

(Figure 1). range, were found. In this way, the value of the Wz parameter for the points lying along one narrow (0.1 mm width) strip was For the presented example, the testing sample begins around calculated using Equation (1). 75 mm toward the warp and around 10 mm in the weft direction. Figure 4b shows the selected fragment of the scanned fabric that has been subjected to geometrical analysis. In the presented 3. Results and discussion fragment, the individual scanning lines are clearly visible in the directions of both the warp and the weft. It can also be seen The results of the calculations are presented in Figure 6. The that practically the entire surface is covered with measurement average value of Wz for all strips in the direction of the weft was points (in total, the point cloud of this fragment consists of Wz weft = 0.56 mm, while in the warp direction, Wz warp = 0.68; the

296,848 measurement points), except for some fragments average value for all lines was Wz average = 0.64 mm. found on rising or falling surfaces that form the bumps. This is due to the fact that the laser scanner was perpendicular to the The other parameters for this fabric are described as follows: fabric and, when a surface with a large angle of inclination was scanned, much less laser rays fell on it. Ra – it is the average value of height of all points in relation to the fabric thickness: To evaluate the parametric geometry of the seersucker fabric, 1 n Ra = z − zn the Wz parameter proposed by Matusiak and Frącczak [15] was ∑ , (2) n = used. It was determined on the basis of the difference between i 1 the highest peak and the deepest valley in a given measurement where range and is expressed by means of the following relationship: n 5 1 ( − ) z = zn , (3) ∑i=1 H a H in ∑ W = (1) n i=1 z 5 where

Hmax – the value of the highest peak in a given measurement interval, and Hmin – the value of the deepest valley in a given measurement range.

The value of Wz– according to the definition – refers only to a single curve, whereas the fabric is spatial. Considering this, for the seersucker woven fabric at work [14], the line was projected onto the surface of the fabric and several dozen lines were analyzed in the warp and weft directions. The width of the fabric part with the lines was determined in such a way as to cover the entire repeat of the seersucker effect and was determined Figure 6. The value of Wz for individual lines: 1 – along the thread; separately for each of the analyzed directions. 2 – along the warp.

a) b)

Figure 5. Narrow strips cut from a point cloud to analyze the Wz parameter: a) along the warp; b) along the weft. http://www.autexrj.com/ 246 AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX

where zn is the height of a given measurement point. For the variability was smaller and ranged from 0.45 mm to 0.76 mm, analyzed sample, Ra = 0.32 mm. with an average value of 0.56 mm. The average value of the Wz parameter for the whole fabric was 0.64 mm.

Wmin, Wmax – the minimum and maximum heights of the fabric. The point cloud representing the fabric scan was set in such a As we can see, the parameter showed high variability depending way that the lowest scanned point had a value of zero; thus, on the direction in which it was measured (Figure 6). In the

Wmin = 0, while Wmax = 2.35 mm. warp direction, it resembles a sinusoidal shape. This is due to the fact that the full seersucker effect repeat consists of one

The next stage of the analysis was to check the quantitative puckered strip and one flat strip. The values of theW z parameter allocation of points to the individual height ranges of the for both kinds of strips are different. This was also stated in seersucker woven fabric. For this purpose, it was decided to a preliminary investigation [15]. It is worth emphasizing that divide the investigated seersucker fabric into intervals with a the maximum value of the Wz parameter occurred in regions height of 0.2 mm. The results of this analysis are presented in where the height of puckering was the highest; therefore, we Figures 7 and 8. The analysis showed that the most numerous can determine this value as the maximum puckering effect in interval is in the range of 1.0–1.2 mm. However, most points a given measurement range. It is also worth noting that the were in the range of 0.6–1.4 mm. “measurement lines” were spaced apart from each other, every 1 mm. Therefore, it was additionally possible to approximately Based on the measurements carried out, it can be concluded determine the actual width of the flat and puckered strips, that for the fabric being tested, the distance between the lowest which were 11 mm and 15 mm, respectively. point and the highest point was 2.35 mm. In turn, the value of the

Wz parameter changes depending on the analyzed direction: As can be seen on the hypsometric maps (Figure 7k and j), for the warp direction, it varied from 0.11 mm to 1.52 mm, with higher puckered places can occur in different parts of the an average value of 0.68 mm, while in the weft direction, the measurement surface. On the other hand, the Wz parameter is

a) b) c)

d) e) f)

g) h) i)

j) k) l)

Figure 7. Hypsometric maps showing the distribution of the fabric measurement points in terms of individual height ranges (data in mm): a) 0–0.2, b) 0.2–0.4, c) 0.4–0.6, d) 0.6–0.8, e) 0.8–1.0, f) 1.0–1.2, g) 1.2–1.4, h) 1.4–1.6, i) 1.6–1.8), j) 1.8–2.0, k) 2.0–2.2, and l) 2.2–2.4. http://www.autexrj.com/ 247 AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX

0 0,2- 0,4- 0,6- 0,8- 1,0- 1,2- 1,4- 1,6- 1,8- 2,0- 2,2- 0-0,2

Frequency measurements;of % 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0 2,2 2,4 % 1,85 5,46 7,17 12 19,5 23,5 15,3 5,19 4,7 3,39 1,49 0,32 Height range; mm

Figure 8. Number of measurement points located within particular fabric height ranges. closely related to the height of the seersucker strips; therefore, and the average value of the puckering. However, on the basis its value changes depending on which fragment is selected of the share of the individual measurement points in the given for surface analysis. Such variability will also occur in the weft height ranges, it is possible to determine what percentage of direction. However, this variability is much less significant, the total area of a given seersucker woven fabric is created by since this parameter is measured along the whole fabric and the seersucker strips. so the measurement includes both puckered and flat strips.

The Wz parameter itself is not sufficient to fully determine the 4. CONCLUSIONS level of the seersucker effect on the seersucker woven fabric, e.g., it does not include the quantitative contribution of the This paper presents a proposal for the parameterization of a puckered parts in the total surface of the fabric. In this case, seersucker woven fabric. The scanning method is very similar we can use the hypsometric maps and divide the entire point to that proposed by Matusiak and Fracczak in their preliminary cloud into individual intervals, simultaneously determining the investigations [15], with the difference that in this paper, the number of points in the individual ranges (Figures 7 and 8). geometric analysis was conducted using a point cloud rather For the analyzed fabric, the most number of points was in the than the previously processed scanned surface. As a result, ranges from 0.6 mm to 1.4 mm, which is about 70% of all points. two steps were eliminated: creation of a surface geometry, and It is related to the fact that in this height range, apart from the projection of the lines onto the surface in order to measure the convex places, there are also flat parts of the fabric, while individual values of the parameter Wz. An additional benefit of below this range (about 14% of all points), there are concave using the scanned point cloud is that it is possible to determine places (valleys) of fabric. It should also be emphasized that in other structural parameters, such as the maximum height of the selected fabric area, the flat part was divided into several the sample to be tested and the average roughness value ranges, which indicates the inclination and unevenness of the (Ra), or create hypsometric maps. The proposed method flat part of the seersucker fabric. of measurement of the seersucker woven fabrics allows parameterization of the seersucker fabric structure. It is In the graph presented in Figure 8, it can be seen that the part possible to determine the height of the puckered places and associated with the valleys (concave places) is in the lower analyze the relationship between the puckered and flat strips range of height (0.6 mm - from 0 mm to 0.6 mm) than the part within a given measurement range. It is also possible to specify associated with the top regions (peaks) of the puckered part the percentage share of points in the individual height ranges. (from 1.4 mm to 2.4 mm – 1 mm). This indicates the flattening of the fabric in the layer with the valleys, which is related to the fact that the fabric is grounded in the measuring table at the ACKNOWLEDGMENT most concave places of the seersucker strips. This work was financed by the National Science Centre, Summing up, it can be concluded that using the values of the Poland, within the framework of the project titled “Geometrical,

Wz parameter presented and discussed herein, it is possible Mechanical, and Biophysical Parameterization of Three- to determine the level of the seersucker effect. It is possible Dimensional Woven Structures”, project number 2016/23/B/ to determine the maximum value of the seersucker effect ST8/02041. (maximum puckering), the real width of the seersucker strips, http://www.autexrj.com/ 248 AUTEX Research Journal, Vol. 19, No 3, September 2019, DOI: 10.1515/aut-2018-0042 © AUTEX

[10] Mohri, M., Hosseini Ravandi, S. A., Youssefi, M. (2005). References Objective evaluation of wrinkled fabric using radon transform. Journal of Textile Institute, 96(6), 365-370. [1] Badawi, S. S. (2007). Development of the weaving machine and 3D woven spacer fabric structures for lightweight [11] Semnani, D., Hasani, H., Behtaj, S., Ghorbani, E. (2011). composites materials. PhD Thesis, Technical University of Surface roughness measurement of weft knitted fabrics Dresden, Dresden, Germany. using image processing. Fibres & Textiles in Eastern Europe, 19, 3(86), 55-59. [2] Unal, P. G. (2012). 3D woven fabrics. In: Jeon, H. Y. (Ed.). Woven fabrics. Rijeka, InTech 91-120. [12] Modrak, J. (2012). Evaluation of change in structure of nanofibre membrane surface during washing cycles. [3] Matusiak, M., Sikorski, K., Wilk, E. (2012). Innovative Degree thesis, Technical University of Liberec. woven fabrics for therapeutic clothing. In: Bartkowiak, G., Frydrych, I., Pawłowa, M. (Eds.), Innovations in textile [13] Vik, M., Vikova, M. (2014). Surface topography of textile materials & protective clothing. Warsaw, CIOP-PIB,. 89- braille labelling. Proceedings of the 7th International Textile, 106. Clothing & Design Conference – Magic World of Textiles, Dubrovnik Available from: https://www.researchgate.net/ [4] Gandhi, K. (2012). Woven textiles principles, technologies publication/270957631_Surface_Topography_of_Textile_ and applications. (1st ed.). New Delhi, Woodhead Braille_Labelling [accessed Aug 07, 2018]. Publishing, pp.142-158. [14] Mooneghi, S. A., Saharkhiz, S., Varkiani, S. M. H. (2014). [5] Maqsooda, M., Nawaba, Y., Javaida, M. U., Shakera, K., Surface roughness evaluation of textile fabrics: A literature Umaira, M. (2014). Development of seersucker fabrics review, Journal of Engineered Fibers and Fabrics, 9(2), using single warp beam and modelling of their stretch- 1-18. recovery behavior. The Journal of the Textile Institute, 106(11), 1154-1160. DOI: 10.1081/00405000.2014.977542 [15] Matusiak, M., Fracczak, L. (2018). Investigation of 3D 2014. woven fabric topography using laser-scanning. Fibres & Textiles in Eastern Europe, 26, 1(127), 81-88. DOI: [6] Militky, J. (2012). Woven fabrics surface quantification. 10.5604/01.3001.0010.7801. In: Jeon, H. Y. (Ed.). Woven fabrics, InTech, pp. 121-154. ISBN 978-953-51-0607-4. [16] Matusiak, M., Fracczak, L. (2017). Comfort-related properties of seersucker fabrics in dry and wet state, [7] Militky, J., Bajzik, V. (2002). Surface roughness and fractal International Journal of Clothing Science and Technology, dimension. Journal of Textile Institute, 92, 1-24. 29(3), 366-379. [8] Militký, J., Mazal, M. (2007). Image analysis method of [17] Matusiak, M., Fracczak, L. (2016). Influence of kind of weft surface roughness evaluation. International Journal of yarn on properties of the seersucker woven fabrics. Autex Clothing Science and Technology, 19, 186-193. Research Journal, 16(4), 214-221. [9] Park, K. H., Kwon, Y. H., Oh, K. W. (2003). The surface roughness measurement for textiles fabrics by a noncontact method for tactile perception. 6th Asian Design International Conference.

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