Browsing by Author "Fernando, EASK"

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Analysis of the dimensional change of woven fabrics from loom state to finished state
(IEEE, 2018-05) Kandemulla, KASM; Maduwantha, ARL; Fernando, EASK; Niles, SN; Jayawardana, TSS; Chathuranga, D
Dimensional change of a woven fabric is a challenge in woven fabric production. The phenomenon originates from the dimensional instability of the fabric. Shrinkage is a combined result of numerous factors such as relaxation, dyeing, finishing and the effect of machinery. The significance of this problem has been investigated by several researchers, who focused mainly on the geometry of the fabric during the weaving phase (loom stage) only. To investigate the dimensional changes that occur within a particular woven structure, a number of fabric samples were sent through various finishing processes such as, washing, dyeing & finishing, under the laboratory conditions. The changes were measured either in terms of dimensional change or EPI and PPI values. Using the experimental data and theoretical analysis, a mathematical model has been developed and validated. However initially the focus is laid on plain woven fabrics and it is expected to be further extended to the other woven structures as well.
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Automatic in-line moisture control system for weft package on a weaving machine
Fernando, EASK; Jayawardana, TSS
The competitive woven fabric production moves from shuttle weaving to shuttleless weaving in order to acquire higher production rates in tact with good quality. The efficiency of the loom production not only depends on the loom speed but also on the rate of loom stoppages during the weaving process. The loom stoppages can be occurred due to various reasons and the frequency of such occurrence will determine the rate of loom stoppages. In addition to the reduction in efficiency, loom stoppages seriously affect the fabric quality as startup marks and differential dye take up are appeared on the fabric as defects. The ambient conditions in the vicinity of the weaving machine is subjected to vary over the day due to the heat dissipation from weaving machines and many other reasons such as sunlight and prevailing weather conditions. In the weaving preparational process, warps ends are generally sized so that they can withstand various stresses encountered in weaving process. However, weft yarn is not sized to retain greater flexibility and hence it is much susceptible for damages. The possibility of damaging the weft yarn is further influenced by the variations of surrounding conditions and hence these conditions are much sensitive for the weft yarn breakages during weaving process. In this paper, authors attempted to analyze the effect of surrounding conditions to weft breakages in weaving and device an automatic in-line moisture control system for weft package in weaving machine. Based on the experimental evidences, authors verified the effectiveness of the automatic moisture control system and their strong industrial implication in existing weaving machines.
item: Conference-Abstract
Design and fabrication of an automatic tension monitoring and regulation system for needle thread
Randima, LML; Sandaranga, DMBC; Jayawardana, TSS; Fernando, EASK
A matched needle and bobbin thread tensions is a major requirement of a seam and also to the quality of garment. This paper describes an attempt on the development of an automated needle thread tension regulating system for single needle lock stitch sewing machine. Historically, several experiments have been carried out to measure the thread tensions of both needle thread and bobbin thread of a lock stitch machine. However, no evident in favour of the development of a device to adjust the needle thread tension automatically. Despite a cyclic variation of the needle thread tension, a needle thread regulation system is developed to maintain an average needle tension during the cycle at a predetermined level. The developed system can be installed on an existing single needle lock stitch machine and capable of maintaining the required correct thread tension profile for sewing. The needle thread tension regulation system is a closed loop system and with a load cell as a sensing device and a geared DC motor adjusts the compression of the spring of the thread tensioner. A visual display of thread tension is indicated on a 16X4 LCD display and the required needle thread tension is set by 4x4 keypad. An Arduino board controls the electronic equipment in the system.
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Design of a bullet-proof vest using shear thickening fluid
Fernando, EASK; Niles, SN; Morrison, AN; Pranavan, P; Godakanda, IU; Mubarak, MM
Bulletproof vests are used to protect the user from bullets fired at them. Various such vests are currently available and are bullet resistant to a particular threat level. The protection is given by the material used to produce the ballistic panel. Different types of materials can be used to obtain various properties and different strength levels. While the material imparts strength, the amount of material used also affects the protection. The current focus in the market is to produce vests with minimum weight and thickness. The target of this research was to develop a ballistic panel using textile materials. Further, the possibility of using a Shear Thickening Fluid was explored in order to reduce the amount of textile fabric used.
item: Conference-Full-text
Design of a weft gripper system for required weft tension on rapier loom
(2006) Gopura, RARC; Gunasekara, JMP; Fernando, EASK
In an existing rapier loom, when the rapier comes out from the shed, the tension of the weft yam changes before the reed reaches the fabric fell. Also in case of elastic yam, a certain length of the yam may retract due to the elastic nature of the yam. With the existing systems of rapier looms, weft yam tension cannot be controlled until the weft is interlaced into the fabric. Because of the above reasons the quality, selvage and appearance of the fabric could be impaired.
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Designing of tension control Device to minimize tension variation across Weaver’s beam
Fernando, EASK; Jayawardana, TSS
The tension variations across the width of the weaver’s beam cause uneven tension in the fabric formation zone. As a result of the tension variation, the woven fabric tends to have fabric defects, such as non-uniform fabric density and differential dye take–up at various places on the fabric. As the warp ends are continuously subjected to varying tensions, warp breakage frequently occurs. As a result, the quality of the fabric produced suffers and there is reduced loom efficiency. However, uniformity in the fabric density is crucial, especially for technical and smart textiles. In this paper, the authors have attempted to model the varyingtensions across different segments of a warp sheet under a set of assumptions and derived a linear model. Furthermore, a prototype of an automatic tension control device is instrumentedwith two different positions which are located one meter apart and allows the tension variations across the warp-sheet to be practically observed. The measured average tension shows that variations in the internal tension on different segments of the warp-sheet can be minimized or even completely eliminated over time. With the implementation of a related experiment, the authors have shown the effectiveness of this automatic tension controller and its strong implications for the industry.
item: Conference-Full-text
Developing a technological process to weave cotton fabrics on water jet loom
(IEEE, 2016-05) Prasanna, MAAU; Senanayake, SS; Wijesinghe, SAKP; Fernando, EASK; Perera, SAS; Jayasekara, AGBP; Bandara, HMND; Amarasinghe, YWR
Water jet looms are widely used in woven fabric manufacturing especially for synthetic fabric production. Due to massive growth in synthetic fabric production, the significance of the water jet loom becomes dominant Due to its salient features such as high production speed, low energy consumption, low noise emission, and simple maintenance procedures as compared to other loom counterparts. The major drawback of the water jet loom is its inability to produce cellulosic based fabric such as cotton because cotton yarns absorb considerably higher amount of water during weft insertion and as a result it does not properly insert through the warp sheet. Air jet weaving machine is ideal to produce cellulose based fabrics. However, air jet looms lacks in the above advantages possessed by water jet looms. For a sustainable development in the weaving industry and a competitive edge in weaving, it is mandatory to have minimum energy consumption when producing cellulose based fabrics. So, it is prudent to explore the possibility of weaving cellulosic based fabrics on a water jet loom. Hence, the authors attempted to develop an appropriate technological process to achieve this. A non-absorbent cotton yarn was developed and a water jet loom was modified in order to successfully produce cotton based fabrics on a water jet loom.
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Development Of mathematical model to select best technological parameters In sizing
Fernando, EASK; Jayawardana, TSS
The sizing process does not add value to the grey fabric, but it is critical to the improvement of weaving efficiency especially for cotton and cotton blend fabrics. With the advent of technology, weaving speeds have been greatly ameliorated and the significance of correct size applications has been thoroughly explored. Since the correct size application is primarily characterized by the size percentage, the technological parameters for proper sizing were chosen through experimental trials and acquired prior knowledge. Thus, a scientific approach to determining the technological parameters is essential to the textile industry. To fulfill the aforementioned need, the authors have developed a mathematical relationship that relates technological parameters involved in size applications. The practical utility of the derived equations were also highlighted. Experimental trials, carried out with poly/cotton yarn on a single yarn sizing machine, confirm the validity of the model developed. Furthermore, empirical findings published in internationally renowned reference books on sizing were also in accordance with the analytical results established. The mathematical relationships developed can be exploited to calculate the optimum parameters of the sizing machine and to obtain the required quality of sized yarn.This approach does not require carrying out costly trials and therefore has positive industrial impacts. Keywords—Mathematical model,
item: Conference-Full-text
Effect of Starch Particle Size Reduction on the Performance of Sized Warp Yarns
(2015-08-03) Fernando, EASK; Paranavithana, T; Dissanayaka, U; Premarathna, W; Atambawa, A; de Silva, N; Tissera, N
The mechanical and physical properties of tapioca based starch are known to vary in relation to physical parameters including the particle size of the starch granules. In this study, ultra sonication was used to reduce the particle size of starch solution from 100μm to 8μm and the modified starch was applied on poly cotton warp yarns. The strength, extension, moisture regain and size add-on% was tested and compared with the properties of conventionally sized yarns. The results showed that better strength and extension properties can be obtained by the application of ultra sonicated size solution at lower drying temperatures and lower squeeze roller pressures with minimum size add-on%.
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Experimental analysis of ground water for its recycling in water Jet Weaving
Fernando, EASK
The rapid increase in synthetic fabric production promotes the development of water jet looms and water jet weaving technology. Water jet looms are particularly characterized by their high insertion speeds and low energy consumption. However, the main drawbacks of these machines are their excessive water consumption that leads to water wastage. Even though water is a finite, valuable resource and should be used in an effective manner, very little research has been focused on the recirculation of used water and the usage of ground water in water jet weaving. Therefore, the author attempts to design a filtering system that can recirculate the water used in water jet weaving. The water quality of ground water has also been analyzed for its suitability in the weaving process. In order to have a uniform weft that minimizes greigefabric defects and mitigates machine damages, an experimental analysis was executed. The acquired data shows the parameters of ground water that should be controlled during recirculation. Finally, an objective assessment of test results was used to develop a suitable, simple, and cost effective filtering system. The system can be utilized to recycle ground water and to minimize both water wastage and consumption in water jet weaving.
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Innovative design of a rotational type heat exchanger
(2008) Gopura, RARC; Fernando, EASK; Amarasena, KGAH
New innovate design of rotational type heat exchanger is proposed. It has ability to work in diverse heat transfer environment, ability to increase heat transfer area and promote turbulent flow. It is self cleaning heat exchanger with easy access for further cleaning of heat transfer element and has easy expandability of the capacity by addition of separate heat exchanger units.
item: Conference-Full-text
Machine learning-based approach for modelling elastic modulus of woven fabrics
(IEEE, 2020-07) Kularatne, SDMW; Ranawaka, RAHS; Fernando, EASK; Niles, SN; Jayawardane, TSS; Ranaweera, RKPS; Edussooriya, C; Weeraddana, CUS; Abeysooriya, RP
There has been a shift of focus from aesthetic properties to mechanical and functional properties of textiles with the recent developments in technical textiles and wearable technology. Therefore, understanding how various fabric parameters influence the mechanical properties of fabrics is paramount. In applications where compression and stretching of fabrics are important, the elastic modulus is a key fabric property that needed to be controlled precisely. Woven fabrics are capable of providing superior elastic properties, but how various fabric parameters affect elastic modulus is not well understood. In this study, two machine learning techniques were implemented to model the elastic modulus of woven fabrics and were compared with multivariable regressions. The two machine learning techniques used are Artificial Neural Network (ANN) and Random Forest Regression. As input variables; weave factor (numerical representation of weave structure), warp yarn count and pick density were used. Both ANN and Random Forest Regression were able to generate reasonably accurate results with Random Forest Regression been the better of the two methods. Using Random Forest Regression, feature importance of the input variables was obtained, and it proved that the weave structure has a notable impact on the elastic modulus of woven fabrics.
item: Conference-Full-text
Mathematical Analysis of Startup Mark in Elastic Tape on a Narrow Fabric Loom
(2015-08-03) Dayaratne, HDCT; Premakumara, R; Perera, T; Prince, S; Fernando, EASK; Jayawardane, TSS
Start-up marks are considered as one of the major defect in woven fabric, it occurs when the loom is restarted after loom stoppage due to various reasons. This defect is more prominent in high speed weaving looms especially with elastic warp yarns and is caused to deteriorate the fabric quality. This research paper deals with the mathematical analysis of the startup mark generation in elastic tape on narrow fabric loom. Mathematical analysis was carried out for both continuous operation condition and under stopping condition of the narrow fabric loom. A system simulation was carried out using the model developed and compared with the experimental results to show the accuracy of the model.
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Mathematical analysis of startup mark in elastic tape on a narrow fabric loom
Dayaratne, HDCT; Premakumara, R; Perera, T; Prince, S; Fernando, EASK; Jayawardane, TSS
Start-up marks are considered as one of the major defect in woven fabric, it occurs when the loom is restarted after loom stoppage due to various reasons. This defect is more prominent in high speed weaving looms especially with elastic warp yarns and is caused to deteriorate the fabric quality. This research paper deals with the mathematical analysis of the startup mark generation in elastic tape on narrow fabric loom. Mathematical analysis was carried out for both continuous operation condition and under stopping condition of the narrow fabric loom. A system simulation was carried out using the model developed and compared with the experimental results to show the accuracy of the model.
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Mathematical model for warp tension with various back rest settings and relationship with technological parameters
Fernando, EASK
In the textile industry, in order to better control loom warp tension and obtain better quality fabrics, it was very pivotal to analyze the influence of mechanical and technological parameters on warp sheet during weaving. When warp ends are continuously subjected to tension variation numerous number of warp breakages may occur and as a result the quality of fabric produced as well as the loom production efficiency is impaired. In the fabric manufacturing process, warp breakages cost in weaving are far higher than in all other stages of production. Uniform fabric density and cover factor in warp & weft way is vital for high quality fabrics such as technical textiles and smart textiles. So author attempt to model the tension in variation along the warp sheet from the weaver’s beam up to the fabric formation zone under set of assumptions in this paper and derived a linear model which can be used to study the behavior of fabric fell. In this study, the effect of the backrest roller type and position on the physical and mechanical properties of fabrics was investigated. Author has measured warp tension with computerized electronic tension device and shown with mathematical module and experimental data, the influence of backrest parameters on weavability.
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Mathematical model to measure energy absorption of a sports bra
(Department of Textile and Apparel Engineering, 2023-08-31) Prasange, VSH; Liyanage, PL; Fernando, EASK; Jayawardena, TSS; Niles, SN; Nandasiri, GK; Niles, SN; Pathirana, M; Madhurangi, C
Measuring the shock absorbency of sports garments is pivotal for ensuring stability and support during exercise, minimizing injury risk in high-impact sports. It assesses a garment's capacity to absorb impact, curbing excessive breast movement and potential harm through compression, encapsulation, and structural support. This evaluation aids in predicting production outcomes and alleviating athletes' discomfort during physical activities. Prior research primarily concentrated on vertical nipple displacement using motion-capture cameras and live models, often neglecting the three-dimensional aspects of breast motion such as velocity, acceleration, and trajectory. This study introduces a novel approach using a sensor system to gather displacement, velocity, and acceleration data at specific points. It employs an artificial model to assess shock absorbency in sports garments during physical activities. The derived mathematical model, based on breast displacement data, offers insights into material and design choices prior to sample preparation. The study's findings yield invaluable insights for sports bra design and development, as well as selecting appropriate options for diverse physical activities. The authors aimed to develop a test method and mathematical model for measuring sports bra shock absorbency, addressing challenges related to cost, accuracy, and complexity. This research strives to enhance understanding and advance the evaluation of shock absorbency in sports bras, contributing to safer and more effective athletic experiences.
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Mathematical model to measure energy absorption of sports bra
(IEEE, 2023-11-09) Liyanage, PL; Prasanga, VSH; Niles, SN; Jayawardena, TSS; Fernando, EASK; Fernando, PR; Abeysooriya, R; Adikariwattage, V; Hemachandra, K
Measuring the shock absorbency level of sports garments is crucial to ensure support and stability during exercise. It allows for the evaluation of the garment's ability to absorb impact and reduce the risk of injuries during high-impact sports activities. Measuring shock absorbency ensures the bra offers compression, encapsulation, and structural support, preventing excessive breast movement and potential injuries. It also helps to make predictions for the sports garment production process and helps to minimize the pain of the athletes during sports activities. The test method involves using a motion capture camera system to analyze the breast displacement level during physical activity, with the sports bra worn by a physical model. Here in this study sensor system is used to gather the displacement, velocity and acceleration data of certain points and created a new artificial model to measure the absorbency level of sports garments and to collect data during physical activities.Analysing breast displacement data creates a mathematical model that predicts material and design before sample preparation. This study helps design and choose sports bras for different activities. This research developed a test technique and mathematical model to quantify sports bra shock absorbency to address cost, accuracy, and complexity.
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Mathematical modeling of weft yarn tension in pirn winding
(2015-08-24) Fernando, EASK; Jayawardane, TSS
Pirn winding is an operation of winding yarn from supply yarn package onto pirns which are used for shuttle weft insertion. Firm and coherent winding tension is required to maintain in the pirn winding process to withstand the high forces produced by the deceleration of the shuttle at the end of each pick and to avoid permanent strains in yarns which will appears as fabric defects in weaving. The package size and its diameter vary due to subsequent winding of pirns. Hence the balloon effect varies and caused to change the thread tension at the winding point of the pirn. The thread tension variation is considerably significant from the first pirn wound from a package to the last pirn wound from the same if no tension controlling mechanism is devised. Placing dead weights on the disc tension controller which adds a tension to take off tension may help to compensate the yarn tension variation to some extent to combat with this problem. However, this is a stepwise manual compensation technique which needs the correct timing of compensation to avoid significant tension variations in pirn windings. The author attempted to theoretically analyze the tension variation in the yarn path of the pirn winding machine and theoretically model the tension variation with and without deadweight placement on the tensioners. Author also verified the accuracy and the validity of the model developed through the experimental results obtained at different locations along the yarn path..
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Measurement of seam puckering and influence of Its causes
Fernando, EASK; Jayawardena, TSS
Seam quality is very important aspect of any form of textile assembly using sewing. The quality of the seam is governed by the seam puckering, which mainly depends on the technological parameters of the sewing machine and fabric specifications. Though this dependency is known in qualitative aspect, very little researches have been focused to investigate the quantitative aspect of seam puckering behavior of the seams. The Phong's shading algorithm based luminosity model was developed to estimate the dimensional parameters from the image of the seam captured and, an investigation has been carried out to analyze the dimensional characteristics of puckered fabric using image processing techniques and neural networks. This objective assessment attempt goes beyond the replacement of conventional subjective puckering evaluation methods of seams and move towards the development of empirical models for the causal effects quantitatively. That is the determination of correct needle thread tension setting which is the most influential machine parameter for seam puckering, for a minimum puckering.
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Method and apparatus to weave a fully interlaced three-dimensional textile structure
(2017) Weerasinghe, S; Osara, ESPV; Senarathna, KKSK; Senarath, SAUK; Fernando, EASK
A method was developed to weave a three-dimensional textile structure by interlacing three orthogonal sets of yarns. In this flexible structure, all yarns are fully interlaced at right angles with each other. A manually operated prototype of a machine that is able to produce a three-dimensional textile structure using the above method was developed. The machine uses the principles of a typical weaving loom. Techniques for the three primary motions of weaving namely; shedding, picking and beat-up are realized by the machine while techniques for warp let-off and structure take-up motions are discussed. All motions of the apparatus are designed to be individually driven with the possibility of linking to work collectively as a further development