Analysis of Polygonal Computer Model Parameters and Influence on Fabric Drape Simulation

Contemporary CAD systems enable 3D clothing simulation for the purpose of predicting the appearance and behavior of conventional and intelligent clothing in real conditions. The physical and mechanical properties of the fabric and the simulation parameters play an important role in this issue. The paper presents an analysis of the parameters of the polygonal computer model that affect fabric drape simulation. Experimental research on physical and mechanical properties were performed for nine fabrics. For this purpose, the values of the parameters for the tensile, bending, shear, and compression properties were determined at low loads, while the complex deformations were analyzed using Cusick drape meter devices. The fabric drape simulations were performed using the 2D/3D CAD system for a computer clothing design on a disk model, corresponding to real testing on the drape tester in order to allow a correlation analysis between the values of drape parameters of the simulated fabrics and the realistically measured values for each fabric. Each fabric was simulated as a polygonal model with a variable related to the side length of the polygon to analyze the influence of the polygon size, i.e., mesh density, on the model behavior in the simulation. Based on the simulated fabric drape shape, the values of the areas within the curves necessary to calculate the drape coefficients of the simulated fabrics were determined in the program for 3D modelling. The results were statistically processed and correlations between the values of the drape coefficients and the optimal parameters for simulating certain physical and mechanical properties of the fabric were determined. The results showed that the mesh density of the polygonal model is an important parameter for the simulation results.

Accurate simulation of draped fabric sheets with nonlinear modeling

This paper reports a numerical approach, based on a nonlinear particle spring model and a collision detection procedure, to simulate the shape of a draped cloth, or a flexible sheet, together with a simple but precise three-dimensional shape reconstruction method for real fabric applications. The latter is utilized to verify the accuracy of the proposed drape simulation model. The drapes of four types of fabric on a cylinder are simulated, and the results are compared with the reconstructed shapes of the same cloths; the results show an excellent agreement. The simulation model is further used to calculate the shapes of skirts of different materials and sizes, and the effects of fabric parameters, length, and waist size are numerically investigated. The results reveal that under the same conditions, the behaviors of different materials are affected by their properties in terms of stiffness coefficients of the springs. The silk skirt looks soft and fluttering; the outer contour curve of the skirt simulated for the polyester fabric appears relatively smoother, but the shape of the cotton skirt seems to be stiffer. The skirt made of fabric of 10% cotton and 90% polyester combines the characteristics of the polyester and cotton fabric.

Development of parametric garment pattern design system

PurposeThe development of a parametric garment pattern design system that utilizes anthropometric data for consumer-oriented garment pattern design.Design/methodology/approachAction list and interactive user interface were developed to design flat garment patterns. Three-dimensional drape simulation was also implemented to verify the fit of patterns.FindingsPatterns generated by the parametric design system developed in this study could be modified easily by providing appropriate anthropometric data regardless of their complexities.Practical implicationsParametric pattern design system can reduce considerable amount of time and cost by replacing the trial-and-error based grading processes.Social implicationsParametric pattern design system can generate customized garment patterns quickly and easily. Therefore, it is expected to contribute to the production of sustainable fashion and textile by reducing the loss of time and resource.Originality/valueA versatile and comprehensive action list structure was implemented to manage the drawing actions of the user. Various numerical analysis methods were also used to maintain the geometrical validity of patterns.

An Efficient Rotation-free Triangle for Drape/Cloth Simulations — Part I: Model Improvement, Dynamic Simulation and Adaptive Remeshing

This series of two papers aim to improve the rotation-free (RF) triangle model previously developed by the authors and apply it for drape/cloth simulations. To avoid a previously un-observed drawback, the membrane strain obtained from the three-node displacement interpolation is replaced by the one obtained from the six-node interpolation. Dynamic simulations are made possible by explicit time integration. Instead of using dense structural meshes, the quality of draped patterns is improved by global adaptive remeshing. The works in this paper provide important and necessary techniques for practical applications of the RF triangle in the drape simulation. In part II, other techniques including collision handling and garment construction are further discussed and some practical applications of garments on still and moving human body model would be presented.

A Finite Element Based Approach for the Accurate Determination of the Shear Behaviour of Textiles with the Picture-Frame Shear Test

Picture frame shear tests are state of the art for determining the shear force vs. shear angle behaviour for in-plane deformation of most technical textiles, such as woven fabrics. Many publications describe this test and the used picture frames. Benchmark tests showed that the measured shearing behaviour for one sample depends on the picture frame used. The shearing rigidity of most textiles is very small compared to the in-plane tensile stiffness, so slight imperfections on the experimental setup have a significant effect on the measured results. During the picture frame test, wrinkles may form on the sample surface during the motion of the picture frame above a critical shear angle. These wrinkles can be described as local fabric buckling. If forming of wrinkles leads to a lower level of internal energy compared to a further shearing of the fabric, local wrinkles occur due to the principle of least action. Because of this effect, the measured shear force above the first formation of wrinkles is inaccurate for describing the exact shearing behaviour of textiles. Another possibility for measuring the shear force vs. shear angle behaviour is the bias-extension test. Here, higher shear angles can be achieved without the formation of wrinkles. Both methods are compared in this paper for different textile samples. The relationship of the shear angle and the applied shear force is an important mechanical value and one of the most important input parameter in numerical drape simulations. The analysis of wrinkles, which occur during textile draping, demands exact input parameters for the simulation. Most important for the drape simulation of technical high-performance textiles are accurate values for the bending and shear behaviours. This paper presents simulation results of the wrinkling during a picture frame shear test. Results show that the input parameter for the shear rigidity delivered by the picture frame shear test do not exactly reproduce the formed wrinkles and are, therefore, not suitable for an exact drape simulation. The underestimation of the shear force vs. shear angle behaviour will be shown with a finite element simulation model. The adaptation of the picture-frame and bias-extension parameters for a proper use in numerical drape simulations are examined.

Experimental Setup to Validate Textile Material Models for Drape Simulation

The simulation of the draping process of dry textiles allows one to predict the occurrence of folds and the local fibre orientations and fibre positions after draping. In this paper the experiments to determine the mechanical material properties of textile structures are discussed. The mechanical material parameters are used as input for the drape simulation on the macro-scale. The numeric material models can be validated by comparing the numeric results with the experimental draping results of a drapeability test with standardized geometries. The further developed drapeability test to validate the material models for textile structures will be presented.