Abstract:

Objective Current research on the simulation of double structure crocheted fabrics is limited to two-dimensional fabrics, and this study focuses on three-dimensional simulation of such fabrics based on fabric geometry. JavaScript and C# programming languages are employed to rapidly simulate double structure crocheted fabrics, enabling diversified and rapid design of such fabrics. This work aims at the visual display of the design effects, reduced simulation time, and the overall quality and precision of fabric representation.

Method By integrating the lapping matrix model for warp knitting, a lapping motion and yarn threading matrix model for topping-on structure crocheted fabrics is proposed to determine the positions of loops in the fabric. Through the analysis of the structural characteristics of topping-on structure crochet fabrics, three-dimensional annular models of an 8-point plain loop, a 2-point weft-layered loop, a 5-point centipede loop, and an 18-point topping-on structure are constructed under ideal fabric conditions to define the loop morphology. These models are employed to create the codes for three-dimensional structural simulation.

Results The formation of loop arcs in double structure crochet fabrics is essentially a deformation of weft-insertion structures. By combining the warp-knitting lapping digital model to represent needle front lapping and needle back shogging, the width of the loop arc is expressed using the distance of needle front lapping in the lapping digital. A lapping matrix model is established, and combined with the yarn threading matrix model, which is used for the calculation of knitting diagram matrix. During the construction of the loop structure model, the loop structure is studied at a microscopic level. After determining the horizontal and vertical density of the fabric, the distance between two adjacent needles is denoted as G_w, and the distance between two adjacent courses is denoted as G_h. The relationship between the width of the loop arc and G_w is measured, and the width of the loop arc is 3G_w. From the fabric structure, it is evident that the formation of a double-loop structure corresponds to four chain structures in terms of height. The loop control points are determined using experimental results, and the final loop model is constructed. Two different loop fabric processes are designed, including raw materials, knitting structures, and warp cycles. Using C# and WebGL programming, three-dimensional simulations of the two fabrics and their composite fabrics are carried out, and a comparison between the physical images and simulated images is presented for validation.

Conclusion This study accomplishes three-dimensional simulation of both topping-on structure crocheted fabrics and centipede loop fabrics. A composite design integrating these two fabric types is developed and rapidly simulated, providing novel approaches for efficient and diversified design of such specialized textiles.

Key words: knitted fabric, crochet, fabric model, three-dimensional simulation, double topping-on structure, centipede loop structure