Drape simulation of textiles is a field of research, which is known in the clothing sector for a long time. The ongoing development of high-performance composites made of textile reinforcements and matrix materials focus the interests on a serial production in many industrial sectors, such as aviation and automotive industries. Challenges occur mainly in the serial production technologies and in supplying concepts for the preform architecture and shape. Research aims on the acceleration of preform manufacturing and the reduction of expensive pretests. Numerical simulation models can help to improve the composite development chain with structure and process simulation. A special challenge in drape modeling is the bending behavior of textiles. This study introduces a novel approach for modeling single textile layers as laminates to gain a correct mechanical behavior, where all deformation mechanisms are uncoupled. The implementation in the finite element software LS-DYNA Õ is described. An algorithm is introduced which provides the membrane stiffness for each layer of a laminate to fit the measured cantilever bending stiffness of textiles in every bending direction and bending side. The calculated parameters for the laminate formulation result in the requested Downloaded from bending stiffness for the textile layer. The cantilever bending stiffness can be used directly for dimensioning the model.

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PurposeThe aim of the research is the development of 3D virtual models of lower female bodies from scanned data of different body types for computer‐aided 3D product development of loose‐fitting garments.Design/methodology/approachIn order to develop reproducible construction of fashionable/functional outerwear (e.g. ladies’ trousers) on the basis of generated scalable 3D virtual female models, 3D‐CAD methods have to be developed. In doing so, the variable parameters are predefined and the block pattern of a trouser design can be modified by changing the parameters for the variety of trouser models. Two‐dimensional (2D) pattern pieces are then automatically generated and modified if necessary. According to morphological changes, the whole process proceeds automatically up to 2D patterns and thus corresponds to a grading in 3D.FindingsThe generated 3D virtual model and trouser design corresponding to a basic design or block pattern can be offered to the garment industry. The task of the designer or stylist is only to define the intended pattern design on the created trouser shell. Therefore, the approach is also very feasible for pattern makers who are not skilled in computer technology. The goal of this research is to provide an indispensable basis for an effective new technology for the construction of fit‐relevant, loose‐fitting garments, and in doing so, further accelerate the textile chain.Originality/valueThis paper provides methods of creating 3D garment design as well as grading in 3D, based on scalable virtual models of female lower bodies, which are worked out using a new German size designation system. Since the data processed for the generation of virtual models derives from direct scan data from women (taking into account different body types), the targeted German population is reflected.

The use of thermoplastic components with a complex three-dimensional (3D) shape, manufactured efficiently with thermo-presses, has been increased steadily. Flat knitting technology using reinforcing hybrid yarns in the horizontal and vertical direction is especially suited for producing near-net-shape or fully-fashion multilayer weft knitted fabrics – MLGs (abbreviated from the German word Mehrlagengestrick, meaning multilayer weft knitted fabric). The other advantages of manufacturing such MLGs, using flat knitting technology, are reduced waste and desired reinforcing fibre alignment to obtain improved mechanical properties for high-performance applications. Before knitting 3D shaped MLGs, it is necessary to transfer the 3D component geometry into a suitable two-dimensional (2D) pattern cut by implementing parting lines. The use of computer-aided design (CAD) programs enables an effective development of complex components preforms. The generated 2D pattern cuts are analyzed with the consideration of net-shape preforming processes on V-bed flat knitting machines. The development of a segmented take-down system for effective production of 3D MLG preforms is also discussed.

Shows the necessity of developing powerful 3D CAD-systems for the textile and clothing industry. The connection between 2D and 3D CAD-systems enables the user to prepare a collection more quickly and accurately. Applications could be the drape behaviour of the fabric, the deformational behaviour of fabrics when covering defined surfaces and also technical textiles.