In this paper we present the Sylvie three-dimensional (3D) Drape Tester, developed for fabric drape measurements, and its special auxiliary device that exerts dynamical impact on fabrics during draping. In addition, a new draping characteristic, namely the Drape Unevenness Factor, was defined to describe the evenness of the shape of draped textile material numerically. Three special cotton fabrics were woven exclusively for this work. The three fabrics differ only in the twist direction of their weft yarns. The effect of twist directions in woven fabrics and the influence of the applied dynamical impact on drape test results were analyzed. Based on the test results, we also analyze the process of drape formation, offering proposals for modification of fabric behavior models to contribute to better fabric simulations.

Constitutive description of deformations in technical textiles mostly requires some highly nonlinear material law due to the interaction between the orthotropic yarns and the effect of the matrix. Phenomenological models aim to garb the overall (macro level) behavior required for engineering purposes. This paper introduces a new, two-dimensional phenomenological model for technical textiles accompanied with a data acquiring strategy to determine the material parameters involved in the model. It handles the nonlinear stress-strain relation observed in uniaxial tests and take the interactions in the two, orthogonal directions into account. As we aim to introduce a solution applicable at the service level of the loads, our model is inherently elastic, no time dependent or plastic behavior are introduced. The model can be solidly fit to the measured data.

When fiber-reinforced plastic (FRP) components are designed, it is very important to ensure that textiles are formed into complex 3D geometries without folds, and that the reinforcing structure is oriented appropriately. Most research in this context is focused on finite element (FE) forming simulations and the required characterization of textile reinforcements. However, the early stage of the design of FRPs, where kinematic draping simulations are used, is barely considered. In particular, the need for a critical shear angle for the execution and evaluation of kinematic draping simulations is often neglected. This paper presents an extended picture frame test stand with an optical device recording shear-induced deformations with the help of a laser line emitter. Associated hardware and software for detecting and quantifying the fold formation during a picture frame test were developed. With the additional recorded information, a material-specific critical shear angle can be determined, material behaviors can be compared, and FE-based simulation methods can be evaluated. This innovative test stand and the associated software tools will help engineers to decide on suitable materials and improve transparency in the early stages of the design process.

The study aimed to analyze whether the high compression of unique, tight-fitting sportswear influences the clothing physiology comfort of the athlete. Three specific sportswear with different compression were tested on four subjects while they were running on a treadmill with increasing intensity. The compression effect of the sportswear on the body of the test persons, the temperature distribution of the subjects, and the intensity of their perspiration during running were determined. The results indicate that the compression effect exerted by the garments significantly influences the clothing physiology comfort of the athlete; a higher compression load leads to more intense sweating and higher skin temperature.

Yarn unwinding from a package is an essential step in many textile processes. The quality of the yarn is numericallyexpressed mainly by values of mechanical quantities. In the unwinding process viscoelastic properties are the mostimportant ones. They depend on how the yarn is stressed. The quality of the yarn that is being unwound should not bereduced, unless this reduction doesn’t significantly lower the quality of the textile fabric. During unwind the yarn tensionis not constant, but it oscillates within some interval. Even when the yarn is not strongly stressed, the yarn still can breaksometimes. This is why we think that a cross-wound package is not an ideal form of a package and that such packagesaren’t always made without flaws. We strive to achieve as large warping and weaving speeds as possible, therefore ouraim is to improve the theory of cross-wound package unwinding and to find the necessary modifications of the yarnunwinding process.