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The simulative development of clothing and other textile products requires a complete set of material parameters to be provided. Currently, different simulation software providers users with different values and formats for these parameters. This paper provides an overview about the most important values and proposed structures for storing both the raw data and the extracted parameters. The structure is implemented in both JSON and XML formats, allowing integration in proven formats for three-dimensional worlds such as gltf and x3d. Finally, a structure for organization of the raw data of the testing devices is described. Following this structure allows automatic processing, normalization and extraction of the parameters in short time. The goal of the paper is to simplify and unify the exchange of material parameters for textile fabrics.

The pattern changes on the 3D rotary braiding machines (maypole principle with horn gears with full and empty slots) require complex planning of the carrier positions and timing and allow for production of bifurcated and other complex braids with variable cross sections for medical and technical applications. Another common application of pattern changes is to make a visually different pattern for marking of the remaining length of rope when used in a climbing context or for generally lengthened pieces for medical sutures. The development of such samples has previously been done using the trial-and-error method. This paper presents one rule for supporting a more systematic and purposeful trial, which significantly speeds up the development process. After a short review of the related literature, the main theoretical background is given and two practical cases for pattern change are demonstrated. The patterns were developed using numerical simulation before being tested on a real braiding machine. With this paper the authors hope to give some motivation for the remaining braiders in the world to continue working on the development of systematic rules for this complex process.

In the research project presented in this paper, the effects of welding width, pressure force, power, and speed of ultrasonic welding parameters on hydrostatic pressure resistance were examined. A flexible and lightweight PVC-coated hybrid textile material with uniform thickness was used for weather protection purposes. Three main welding parameters at three different levels were selected based on the preliminary test results involving welding widths of 6 and 12 mm. A lapped type of seam was applied for ultrasonic welding and conventional joining techniques. A conventionally sewn zigzag seam was produced using three main factors at two different levels according to the application area. To avoid seam permeability, the conventional seam was sealed with tape by means of hot-air tape welding and subsequently investigated regarding its hydrostatic pressure resistance. The hydrostatic pressure resistance value of the conventional seam was then compared with ultrasonic weld seams of 6 and 12 mm welding width, and its parametric influence on the quality of the seam was analyzed. The result shows that the ultrasonic weld seam with a 12 mm welding width provided a higher hydrostatic pressure resistance than the 6 mm welding width and the conventionally sewn seam. Statistical analyses were also carried out to prove the significant effect of welding process parameters on hydrostatic pressure resistance, whereby the obtained results were statistically significant. A suitable nonlinear numerical model was also developed to predict the hydrostatic pressure resistance.

Modeling fabrics with yarn models makes the fabric structure more realistic in detail. In this paper, a fiber-level rendering method is proposed to simulate different yarns and fabrics. The fibers are divided into three categories: the ply, the loop hairiness and the short hairiness. Geometric tubes are modeled to match these fibers according to the input yarn parameters. Different fibers can be selected depending on the yarn type, which is flexible to reduce the computation amount. Texture mapping is applied to simulate the yarn surface, reducing the memory and time cost of rendering large numbers of fibers. Several single yarns and fabric with different structures are simulated, demonstrating that this is an effective method for fabric modeling and rendering.

An empirical survey was conducted, manually evaluating the relative haptic preference of patterns in weft knitting for winter garments in Mönchengladbach, Germany. Thirty-six patterns were compared in a blind test using ranking orders with respect to six primary hand values (thickness, softness, warmth, weight, stiffness, and smoothness) and general preference for winter garments by 35 participants. Traits of popular patterns included softness and smoothness as well as tucked stitches, rib structures, and float stitches on the surface. On the other hand, unpopular patterns included lace, purl stitches, and ripples.

This paper deals with performance properties related to human thermo-physiological comfort of three-layer textile systems used for the production of outerwear for cold protection. The transfer of heat and fluids through the compound single layers (woven and non-woven) is investigated and compared to the heat and mass transfer of the systems for clothing. Six characteristics are measured for both single layers and systems of layers: thermal resistance, air permeability, water vapor resistance, relative water vapor permeability, the accumulative one-way transport index and overall moisture management capacity. For each of the characteristics, regression analysis is applied to prove or reject the proposed mathematical dependencies between the transfer abilities of the single layers and the respective systems. The results obtained showed that the fluid transfer abilities of the single layers applied in clothing for cold protection strongly affect the fluid transfer ability of the system of layers, while the heat transfer of the system is dominated by the heat transfer ability of the thermo-insulating layer. The proposed approach for assessment of the transfer processes through a system of layers for the production of outerwear for cold protection could be successfully applied in the design of other textile and clothing items, produced by using systems of different textile layers.

This paper presents a comprehensive experimental study, conducted on a series of woven and non-woven fabric samples from different materials (cotton, polyester, and polyamide) and 14 three-layer systems of textile materials, used for production of outerwear clothing for protection from cold. Heat and mass transfer properties, related to the thermophysiological comfort of the outerwear clothing, namely conductive thermal resistance, water vapor resistance, relative water vapor permeability, air permeability, accumulative one-way transport of liquids, and overall moisture management capacity, were determined for the system of layers and the compound single layers. The transfer properties of the single layers were presented as a function of their thickness, mass per unit area, and areal porosity. The transfer properties of the system of layers were presented as a function of the thickness, mass per unit area, and bulk density of the systems. Regression analysis was applied to derive regression equations. The results obtained allowed assessment of the existence and trend of the influence, as well as evaluation of the strength of the dependences.

This paper provides a critical overview about the state of the art in the area of three-dimensional modeling of braided structures. It gives a generalized geometrical approach for modeling braided structures with arbitrary floating length and filaments in the yarn. The approach is tested with large set of structures of different types. Subsequently, one of the simulated geometries is compared with the real geometry of braided tube.

Warp knitted fabrics are widely used in medical and technical applications, as well as for clothing textiles. To predict their properties, it is useful to have knowledge about the yarn geometry and the yarn interactions within these fabrics. The geometrical modelling of warp knitted structures from single bed knitting machines is documented in the literature. This text concentrates on a computation of the geometry of warp knitted structures, which have complex 3D forms or which are draped over similar ones. The topological information about the structure produced on the machine, is used to create the basic geometry of this structure. After creating the basic geometry, it is transferred to a 3D deformed state of the relaxed fabric. The paper starts with a short overview of the research papers about simulation of warp knitted structures. General theoretical remarks about the transformation from basic structure to 3D structure are given. Examples of spacer fabric with constant or non-constant thickness and tubular fabrics are included. All the results concentrate on the topological representation of the geometry and at this stage do not take into account the influence of internal and external forces exerted on the fabric.