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At present, warp-knitted yarn-dyed shirt fabric has become the research focus due to its comfort and highly efficient production. In order to shorten the development process of warp-knitted yarn-dyed shirt fabric, a computing method including theoretical modeling and simulation is proposed in this paper to simulate 2–5 guide bar warp-knitted yarn-dyed shirt fabric. Based on the structure model of warp-knitted fabric, a new model of geometric shape, including loops and underlap, is built according to size measurement results of the loops. In terms of the establishment of mathematical models, such as models of yarn-pressing, loop types, loop locations, guide bar threading, color and fineness, the transformation between knitting technology and mathematical language is realized. With the double buffer technique of HTML (Hypertext Markup Language), loops and underlaps of each bar are displayed separately on different canvases superposed in some order. Simulation is implemented for 2–5 bar warp-knitted yarn-dyed shirt fabric via JavaScript and C# programming languages. The results indicate that this method is able to simulate diverse 2–5 bar warp-knitted yarn-dyed shirt fabrics in a short time. The pattern effect can be seen with a high similarity and practicability before it is produced, thereby shortening the development.

PurposeThe size prediction of garment is an important part in the process of the garment design and production, and it is also one of the most important features in warp-knitted computer-aided design system. The purpose of this paper is to realize the auto-generation of the garment templates using JavaScript and WebGL technologies, based on the prediction of the size of warp-knitted seamless sportswear.Design/methodology/approachThe warp-knitted jacquard technology is used to produce the warp-knitted seamless sportswear, which is divided into suits and tights. In order to achieve the purpose of this study, the dimensions of four kinds of jacquard patterns knitted under different knitting conditions are measured and the crosswise and longitudinal size shrinkage percentages are also calculated. Then, the relationship between the yarn count and the drawing density as well as the size shrinkage percentage is studied and a size prediction model for warp-knitted jacquard fabric is established. Next, according to the results of the size calculation, the point positions of the garment boundary in the mathematical coordinate system is determined. The color formula is built by the two-dimensional mathematical matrix. Finally, combined with the coordinate position and color information, the template can be drawn automatically.FindingsBased on the size prediction model of warp-knitted garment, the template generation of warp-knitted full-form sportswear on WebGL-enabled web browser is realized, which is proven to be an effective computer-aided design method for warp-knitted garments.Research limitations/implicationsBecause of limited researches, only two groups of yarns and four kinds of jacquard patterns were studied. A vaster database should be built and smooth curve, accurate coordinate needs to be optimized in the further research.Practical implicationsThe size prediction model for warp-knitted jacquard garment and garment template auto-generation of warp-knitted computer-aided design system will simplify the fabric technical design process, shorten design time and improve the efficiency of new product development.Social implicationsThe size prediction model for warp-knitted jacquard garment and garment template auto-generation of warp-knitted computer-aided design system will provide the industries a guidance for new sample development and it also can shorten the development time and lower cost.Originality/valueThis author analyzes the relationship between the size characteristics and knitting technology of warp-knitted jacquard patterns, proposes a model of size prediction and realizes the auto-drawing of the garment template in the warp-knitted CAD system, which provides a reference for the new product design and development of warp-knitted seamless sportswear.

The purpose of this paper is to geometrically simulate warp-knitted medical tubular bandages with a computer-aided simulator. A flat mesh model is established according to unfolded fabric considering the knitting characteristics of double-needle bed warp-knitted tubular fabrics. Moreover, a 3D (three-dimensional) mesh model corresponding to the actual product shape is created. To better describe the spatial geometry of stitches, eight-point models are introduced, and stitches are generated with the flat mesh model. Founded on matrix operations, the stitch position in the 3D mesh model is determined through coordinate mapping. Various stitch paths are rendered in computer programming languages C# and JavaScript to conduct simulations. Warp-knitted medical tubular bandages with a large number of shapes are effectively modeled.

To simulate a warp-knitted product with a specific shape, a mesh-based model for modeling and simulation is proposed. The three-dimensional geometry of the final fabric is represented as a set of polygons, each of them containing information about the 3D orientation of the yarns in the warp knitted structure. Using spatial mapping, stitch coordinates are transformed from the flat mesh model to the three-dimensional mesh model and the final rendering is accomplished. The method provides yarn level data for the complete structure and can be used for speeding up the design process of clothing with warp-knitted products. Several challenges with the larger data amount and possible ways for their solutions are discussed.