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Uses Newmark’s method to carry out a time‐stepping finite element analysis to predict the behaviour of a cloth garment as it falls from an initial horizontal position to a final position draped around a human body form. Bases the finite element model on a simple beam element, in order to minimize the computational time. Accounts for large displacement behaviour by including the element geometric stiffness. Bases the body form on anthropomorphic data produced by a shadow scanner. Enlists a novel scheme to model the contact between the cloth and the underlying body form. Uses the finite element model to provide data for an animated display and finds that it produces sufficiently realistic results for the garment designer’s purposes.

Experiments have been carried out to determine the magnitude of static hole errors for holes of various diameters and depths. A new approach is tried to the problem of extrapolation to zero hole size for the purpose of obtaining a true value of static pressure. The results obtained are in broad agreement with previous experimental data and confirm the fact that a positive error is obtained for deep static holes, whereas shallow holes with large cavities behind them can involve negative errors. Since the effects of hole size and hole depth are apparently opposite, the use of fairly shallow holes can result in pressure measurements which are very close to the true value, provided that in drilling the holes no distortion of the duct wall is produced and all burrs are carefully removed. This point may be of interest in some engineering applications where the material used in the construction of the duct or model is thin.

The purpose of this paper is to conduct a survey on research in fabric and cloth simulation using mass spring model. Also in this paper some of the common methods in process of fabric simulation in mass spring model are discussed and compared.

This paper reviews and compares presented mesh types in mass spring model, forces applied on model, super elastic effect and ways to settle the super elasticity problem, numerical integration methods for solving equations, collision detection and its response. Some of common methods in fabric simulation are compared to each other. And by using examples of fabric simulation, advantages and limitations of each technique are mentioned.

Mass spring method is a fast and flexible technique with high ability to simulate fabric behavior in real time with different environmental conditions. Mass spring model has more accuracy than geometrical models and also it is faster than other physical modeling.

In the edge of digital, fabric simulation technology has been considered into many fields. 3D fabric simulation is complex and its implementation requires knowledge in different fields such as textile engineering, computer engineering and mechanical engineering. Several methods have been presented for fabric simulation such as physical and geometrical models. Mass spring model, the typical physically based method, is one of the methods for fabric simulation which widely considered by researchers.

The purpose of this paper is the application of a tool to assist the multi-criteria decision-making process for selecting an asset for a company in the metallurgical industry which manufactures metal parts for diverse industries.

This investment, complex due to the commitment of resources it requires, has been made with the assistance of decision-making methodologies, specifically versions I and IV of the ELECTRE method.

This model of multi-criteria decision making has been chosen over other models because it offers the possibility of including technical and economic decisions so they can be analyzed simultaneously, therefore the decision is not based solely on financial aspects. Many companies base their decisions exclusively on financial returns, however in this case it is also appropriate to include the technical parameters, since the asset being replaced is the most important asset of the company.

Applying version I of the methodology, the optimal technical configuration of the asset will be analyzed based on the features requirements, all of which are among options available in the market. Once a subset of technically and economically viable alternatives has been defined, version IV will be applied and a ranking of the alternatives from the best to the worst will be obtained and, based on this ranking, the final decision will be made.

Under this heading are published regularly abstracts of Reports and Memoranda of the Aeronautical Research Council and publications of other similar Research Bodies as issued.

The purpose of this paper is to focus on the development of a thorough method for the macromechanical analysis of fabrics.

The homogenization method was implemented for the generation of continuum equivalent model for the plain woven structure. Keystone of the method is the mesomechanical analysis of the textile unit cell for the evaluation of the apparent properties and the generation of an equivalent macromechanical model supporting the mechanical performance of the structure. The finite element method (FEM) using beam elements was applied for the mechanical analysis of the discrete model of the unit cell and the FEM using shell elements was applied for the analysis of the continuum macromechanical model.

The tensile, shear and bending test of the unit cell were simulated. The constitutive equations of the continuum model were formed considering equivalent performance with the discrete model.

The reliability of the equivalent model in tensile, shear (in‐plane) and bending (out‐of‐plane) deformation was achieved even for asymmetric woven structures. The low computational power demanded for the meso‐ and macro‐mechanical modelling and analysis is a beneficial feature of the proposed method.

Undesirable effect of asymmetric drape often occurs when cutting patterns of flared skirt on cross. Out of this reason garment seams twist toward the front or back or folds form different shapes on each side of the garment and this lowers garment aesthetic appearance. The new measuring procedure for asymmetric skirt drape near the side seam, based on bottom traces geometry, was developed in this paper. The experiment with four‐gored skirts of six lightweight fabrics was made. It was found that asymmetric drape depends on combination of grain lines directions of front and back panels of a skirt. There were made general conclusions relating skirt asymmetric drape with various fabric characteristics, such as bending rigidity, extensibility, shear rigidity, fabric weight and drape coefficient in this article. According to developed measuring procedure a final objective evaluation of skirt asymmetric drape rate will be done further.

The identification of the jet propulsion forces from those of the aerodynamic forces of body to which the propulsion system is fitted, is still one of the most controversial subjects involved in aircraft performance predictions and thrust/drag flight test results. In fact the inter‐action between airframe and engine aerodynamics makes the use of independent airframe and propulsion performance impossible.

Some areas of the apparel industry, such as folding and sewing, are still labor intensive. The purpose of this paper is to present a new fuzzy visual servoing strategy for the folding of fabric strips by robotic manipulators.

Three stages of the folding task are distinguished experimentally, the initial laying, the true folding, and the final laying. An indirect visual servoing fuzzy system, employing two cameras, is developed to guide the robot along each of the stages.

The proposed scheme manages to successfully fold some of the tested materials. The experimental results are promising and well within the limitations posed by both the employed equipment and the nature of the handled materials.

This study is limited to rectangular strips of fabrics and does not consider the speed of the process.

The resulting system provides a stepping stone for the introduction of automation to currently labor‐intensive areas of the apparel industry.

The separate folding stages reduce the complexity of the overall system and the introduced visually extracted features allow a closer monitoring of the process.

Virtual maintenance simulation is of great importance to help designers find and avoid design problems. During its simulation phase, besides the high precision requirement, collision detection must be suitable for all irregular objects in a virtual maintenance environment. Therefore, in this paper, a collision detection approach is proposed based on encapsulation for irregular objects in the virtual maintenance environment.

First, virtual maintenance simulation characteristics and several commonly used bounding boxes methods are analyzed, which motivates the application of encapsulation theory. Based on these, three different encapsulation methods are oriented to the needs of simulation, including encapsulation of rigid maintenance objects, flexible maintenance objects and maintenance personnel. In addition, to detecting collisions accurately, this paper divides the detection process into two stages. That is, in the first stage, a rough detection is carried out and then a tiny slice space is constructed to generate corresponding capsule groups, which will be redetected in the secondary stage. At last, several case studies are applied to illustrate the performance of the methodology.

The automatic construction algorithm for bounding boxes can be adapted to all forms of objects. The number of detection primitives are greatly reduced. It introduces the reachable space of the human body in maintainability as the collision search area.

The advantages of virtual maintenance simulation could also be advantageous in the industry with further studies. The paper believes this study is of particular interest to the readers of your journal.