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Development of a technique for weaving seamless three‐dimensional shapes directly on loom is an essential step in producing seamless woven garments. The purpose of this paper is to report a new approach to weaving seamless three‐dimensional shapes.

Spacing of warp and weft threads varies in shape region. Reeds with shaped reed wires are developed to change spacing of warp threads. Interlacement pattern of warp and weft threads is selected that assists in changing spacing of threads. The new approach of weaving three‐dimensional shapes in folded form is developed, that offers advantages over weaving shape in erect form.

The main findings were mathematical determination of shapes of reed wires to produce a three‐dimensional woven shape and weaving shape in folded form.

The paper demonstrates how three‐dimensional shapes are woven in folded form without the need of eliminating ends.

Proposes an algorithm for the computation of maximum needle penetration force; it introduces the direct dependence of penetration force on fabric structural parameters and warp and weft geometrical and mechanical properties. Uses the approach to the simulation of local deformation of woven material which accounts for the thread resistance to crimp change and friction forces when the thread is shifted from its original position in the fabric structure as the result of its interaction with a needle. The resistance of threads to tension caused by a needle pushing them from their straight‐line paths is also accounted for. The resulting formulae give the dependence of needle penetration force for a plain‐woven fabric on the following parameters: needle diameter and surface angle; warp and weft spacing, dimensions, crimp height and bending rigidity; friction coefficients thread‐thread and thread‐needle. For a non‐plain‐woven fabric the linear dependence of penetration force on the fabric tightness is suggested. The comparison with the published and specially measured penetration force data proves the predictive ability of the model to be qualitatively accurate and quantitatively reasonable.

The purpose of this paper is to investigate the effect of materials, three dimensional (3D) structure and number of fabric layers on ultraviolet protection factor (UPF), air permeability and thickness of fabrics.

Total 24 fabrics samples were developed using two 3D structures and two weft materials. In warp direction cotton (CT) yarn and in weft direction polypropylene (PP) and polyester (PET) were used. Air permeability, thickness and UPF testings were performed and relationship among fabric layers, air permeability, thickness and UPF was developed.

UPF and thickness of fabrics increases with number of fabric layers, whereas air permeability decreases with the increase in number of fabric layers. Furthermore, change of multilayer structure from angle interlock to orthogonal interlock having same base weave does not give significant effect on UPF. However, change of material from polyester (PET) to polypropylene (PP) has a dominant effect on UPF. Minimum of three layers of cotton/polyester fabric, without any aid of ultraviolet radiation (UV) resistant coating, are required to achieve good. Cotton/polyester fabrics are more appropriate for outdoor application due to their long-term resistance with sunlight exposure.

Long-term exposure to UV is detrimental. So, there is need of proper selection of material and fabric to achieve ultraviolet protection. 3D fabrics have yarns in X, Y as well as in Z directions which provide better ultraviolet protection as compared to two dimensional (2D) fabrics. In literature, mostly work was done on ultraviolet protection of 2D fabrics and surface coating of fabrics. There is limited work found on UPF of 3D woven fabrics.

When the Euco Ground Thread Micrometer Spacing Collars were introduced a few years ago, the only sizes produced were for 1 in. and 1¼ in. arbors and the minimum width 13/16 in, A few months later, the company extended the range to cover 1½ in. dia. arbors and introduced a narrow type micrometer spacer having a minimum width of ¼ in., also available for arbors up to 1½ in. dia. Continental inquiries resulted in the range being extended to cover 16 mm., 22 mm., 27 mm., 32 mm., 40 mm., 55 mm. and 60 mm. with metric calibrations 001 mm. As many foreign industrial concerns were using British and American machines, a further demand developed for the English sizes with metric readings, so the range was again extended.

The purpose of this paper is to design woven fabrics with desired quality and low manufacturing cost by optimizing the weave parameters such as count, crimp and thread spacing of warp and weft yarns.

To fulfill this goal, the authors endeavor to devise a searching mechanism based on particle swarm optimization (PSO) for efficiently finding the appropriate combination of weave parameters.

The experimental validation confirms that the proposed method has an excellent search capacity to obtain the best combinations of weave parameters for producing the fabrics with requisite quality at low cost.

The quick response capability of the system would benefit the fabric manufacturers for efficient determination of the required weaving parameters to produce the engineered fabrics.

This paper offers a maiden application of PSO technique to design engineered products in textiles. The method is easy to implement and it is computationally inexpensive as fewer parameters are involved.

The mechanism of strength reduction of sewing threads has been discussed in Part I of this paper. The effect of fabric tightness and certain thread properties like its size, coefficient of yarn‐metal friction, twist direction, number of piles, type of fibre and fibre denier on strength reduction has been studied and found to influence the severity of strength reduction of the thread.

The purpose of this paper is to establish a simple and practical elastica model for the deflection of weft (warp) in a plain wave fabric.

The weft yarn is considered as an elastic beam fixed supported at the ends and deflected in the middle by a vertical load. An analytical model, based on the elastic theory and small deflection case is adopted to study the factors affecting the deflection of the yarn. To investigate the model, yarns with different rigidities are used. A total of five different yarn counts are produced in the same ring spinning system and then used as weft yarn in a plain weave fabric. All other parameters of the yarns and the fabrics are kept identical. Fresh fabrics are analyzed and the maximum deflection of the weft is measured using the microscope. The actual curves of the deflected weft are then compared with the theoretical curves.

The experimental curves show to agree well with the theoretical model. The results also show that as yarn linear density decreases, the deflection increases.

The paper shows that while the large deformation “elastica” theory is typically used for woven fabric modeling, the small deflection theory can be useful for rapid computation.

The surface of the textile fabrics is not absolutely flat and smooth. Its geometrical roughness within certain extents is considerable. The surface roughness influences the fabric hand and it plays a significant role in the end use of the fabric. In parallel, the periodic variations of the fabric surface level due to the regular interlaced patterns of the yarns cause a respective variation of the geometrical roughness measurement. Thus, the fabric roughness data measured using the Kawabata Evaluation System for Fabrics and imposed to a certain process of numerical calculations result into the retrieval of the structural parameters of the fabric. The principle of the method has a non‐destructive character and can be applied to woven or knitted fabrics.

The objective of this paper is to report the values of thermal resistance in natural and convection heat transfer modes through woven fabrics. An instrument developed on the principle of the guarded hot plate method will be discussed. The instrument is precise up to two decimal places and the accuracy is approximately 14%. The fabrics were tested in a natural as well as forced convective mode with air velocity of 1m/s flowing parallel over the fabric surface. It was observed that the thermal resistance of the fabric in forced convection is less than that in the natural convective mode.

The thermal resistance can be predicted with the help of a statistical model when all the constructional parameters are taken together. A polynomial equation consisting of linear, interaction and square terms based on the response surface modelling was developed for both the conditions of heat flow. It was observed that as all constructional parameters, such as warp and weft count, thread spacing, thickness, fabric weight and porosity are taken as variables, the response function; namely thermal resistance can be predicted with a high coefficient of determination and less average error.

Bending and shear rigidities of woven fabrics depend on fibre, yarn and fabric-related parameters. However, there is lack of research efforts to understand how bending and shear rigidities change in woven fabrics having similar areal density. The purpose of this paper is to investigate the change in bending and shear rigidities in plain woven fabrics having similar areal density.

A total of 18 fabrics were woven (9 each for 100 per cent cotton and 100 per cent polyester) keeping the areal density same. Yarns of 20, 30 and 40 Ne were used in warp and weft wise directions and fabric sett was adjusted to attain the desired areal density.

When warp yarns become finer, keeping weft yarns same, bending rigidity remains unchanged but shear rigidity increases in warp wise direction. When weft yarns are made finer, keeping the warp yarns same, both the bending and shear rigidities of fabric increase in warp wise direction. Similar results for fabric bending and shear rigidities were obtained in transpose direction. There is a strong association between fabric shear rigidity and number of interlacement points per unit area of fabric even when fabric areal density is same.

Very limited research has been reported on the low-stress mechanical properties of woven fabrics having similar areal density. A novel attempt has been made in this research work to investigate the bending and shear rigidities of woven fabrics having similar areal density. Besides, it has been shown that it is possible to design a set of woven fabrics having similar bending rigidity but different shear rigidity.