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The procedure of computerised automatic construction of a cutting pattern for men’s shirt is presented. It is based on the calculation of construction measures necessary for the calculation of all the construction elements. The procedure of construction is similar to the conventional hand procedure, but is done using a computer, so that the locations of the co‐ordinates of all the principal and auxiliary points on cutting part contours are calculated. Straight segments are drawn afterwards through these calculated points and curved segments interpolated.

This paper propose an algorithm for the multiple silicon steel coils multiperiod two-dimensional lengthwise cutting stock problem (m2DLCSP), so as to minimize the total cost of materials and production.

The authors propose a sequential leftovers utilization correction (SLUC) algorithm for the m2DLCSP. The algorithm primarily considers three optimization strategies. First, it considers usable leftovers to simplify the cutting process and improve material utilization. The total quantity and types of leftovers should be limited in order to avoid leftover overstock. Second, it uses a splice method of items to improve the generated cutting plan. Third, it takes into account operational restrictions in the cutting operations. Operational restrictions include imposing maximum and minimum lengths on the cutting patterns, and the limitation of cutting knives at the slitting machines.

Several sets of benchmark with real-world and randomly generated instances are provided to evaluate the algorithm. Compared with literature algorithm and current procedure applied in enterprises, the computational results indicate that proposed algorithm can effectively reduce the total cost, and the computation time is reasonable for practical use.

This algorithm can effectively reduce the total cost.

The proposed method can effectively applied to solve the m2DLCSP and improve the economic efficiency of enterprises.

The problems of pattern cutting as applied to flexible elastic mesh fabrics (lace) are described within the context of the total manufacturing process. While the design and knitting stages of lace manufacture are highly computerised, providing associated benefits, the cutting room operates with conventional, slow, labour intensive machinery, leading to substantial processing bottlenecks and dependent costs. A new system is presented which uses machine vision to determine the required cutting path on the lace fabric in real‐time via sophisticated, yet high speed, image processing algorithms. The determined cutting path data are used to direct a high speed CO₂ laser beam to the correct cutting point with beam velocities of typically 6 m/sec. Simultaneous dual edge cutting is now possible using this new system, leading to lace throughput being increased by a factor of ten typically, with the possibility of processing more sophisticated designs and achieving higher cut edge quality.

In this study, a two‐stage algorithm is developed for the cutting sequencing problem in a modular manufacturing system consisting of four basic workstations. Since the flexibility of the system is dependent upon the cutting stage of raw materials, the study focuses particularly on this workstation. In the first stage of the algorithm, an integer linear programming model is used to determine the number of hardboards that will be cut. The model is tested with two different objective functions. In the second stage, a heuristic which takes into account the due date of the products is developed to obtain the real‐time sequencing of these cutting patterns on the shop floor. The algorithm is further implemented in a furniture manufacturer that operates on a make‐to‐order basis. The results of the existing and proposed system are compared, and the proposed algorithm is found to provide a useful tool in such a real‐life planning problem.

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

The method has been developed on an example of a 3D garment basic cut construction on a virtual body model, determining the position of characteristic 3D points necessary for computer‐based definition of 3D cutting pattern contour segments. Contour segments modelling, as well as the modelling of 3D cut surfaces has been done using the NURBS objects.

A 3D garment cut has been constructed, such that matches physical characteristics of the body in question and offers the necessary comfort of the cut. The surface of the 3D cut has been divided into individual 3D cutting patterns.

The method has been developed on an example of a 3D garment basic cut construction of a single paper of clothing. However, the same principles can be applied and developed for any garment basic cut.

The 3D garment cut constructed can be further transformed into a network of polygons. Introducing fabric physical‐chemical properties fabric drape can be simulated, aiming at more realistic visualisation and further assessment of the garment fit. The 3D cutting patterns developed can be, applying computer‐based application of the mathematical models, transformed into 2D cutting patterns.

As compared to the methods developed by some previous investigations, the newly developed method offers the construction of garment 3D cut on a computer‐generated body model, granting the necessary comfort of the cut, which also means garment fitted to individual body characteristics. The 3D cut constructed can also be used as a starting point to define 2D cutting patterns in the following step, which will be matched to the physical characteristics of the model body, in the same way as the initial 3D cut.

The designing and initial alignments of 2D garment patterns in 3D space are the key procedures in 3D apparel design. This paper presents a new methodology to prepare and edit initial pattern shape in 3D space by simulating virtual cloth scissoring.

In conventional apparel CAD tools, flat 2D patterns are drawn and sewn in 3D space. Thus, the final appearance of 3D garment cannot be easily predictable for non‐specialized personnel from the flat patterns. This paper adopts the real pattern designing method of “draping”, incorporating it into computer‐based designing so that the user can realistically cut, sew and add the cloth by only using a mouse. 2D and 3D meshes are edited simultaneously and thus a flattening process is not needed.

Several mesh‐based operations such as cutting, sewing, adding, and fixing are devised and have been successfully applied to virtual garment cutting.

Our new pattern drawing method has an advantage that designer can look and feel the garment appearance interactively during the design process. Virtual cutting is identical to the real pattern draping technique and is easy to adopt for designers.

With current computer hardware speed and through using the drape simulation technique, it was possible to drape and cut cloth in real‐time. In addition, both the 3D pattern and 2D flat pattern could be simultaneously acquired.

To have all the required components of batches of product orders ready for timely assembly and delivery, the real time wood strip cutting patterns in a major solid wood furniture manufacturing plant has to be dynamically generated based on both the order priority and the minimum wood waste.

An adaptive fuzzy ranking method and a recursive function for pattern generation were integrated into an optimization procedure to solve the real time one‐dimensional multiple‐grade cutting stock problem when orders are prioritized.

The simulation results illustrate that the optimization algorithm produce considerably less waste than the current approach. If implemented in the industry, the saving in raw material could be in the range of 5‐10 percent.

The optimization algorithm is for the cut‐to‐size decisions only with the consideration of the order priorities. The overall scheduling of the production shop floor is not addressed.

The algorithm can be used on the cutting machines as an online patterns generator and cutting optimizer.

There is no literature available for the real time one‐dimensional multiple‐grade cutting stock problem when orders are prioritized. The few commercial optimizers have unknown algorithms with unpredictable waste.

To provide an algorithm for the two‐dimensional guillotine‐cutting problem of punched strips.

It is assumed that the stock sheet is cut into blanks in two stages. First a guillotine shear cuts the sheet into strips, and then a stamping press punches out the blanks from the strips. To generate good strip layout, the sheet is divided into two segments with an orthogonal cut. Each segment consists of strips in the same direction. The strip directions of the two segments are perpendicular to each other. A recursion function is established to determine the optimal strip layouts on segments of different lengths. All possible segment lengths are considered either explicitly or implicitly. Two segments of different strip directions are selected optimally to compose the final cutting pattern.

A strip can be taken as consisting of rectangular pieces, where the length of the first piece may be longer than that of the others. Normal lengths and widths can be defined according to the properties of punched strips. Considering only normal segment lengths and using lower bound in the recursion function can reduce the computation time drastically.

Based on the algorithm, practitioners may develop applications to solve real world two‐dimensional cutting problem of punched strips.

The two‐segment cutting patterns for punched strips are proposed. They are simple to cut and may be welcomed in practice.

Designing of clothes using the historical prototypes is very popular in contemporary practice. The purpose of this paper is to apply 2D and 3D computer-aided design (CAD) systems to reconstruct the historical pattern block and get the virtual image in accordance with the prototypes. New algorithm has been proved for men trousers taken from the nineteenth century.

Our approach is to develop a method of CAD to reconstruct historical trousers through analyzing and rebuilding of historical algorithms used to pattern blocks making, old anthropometrical database, and the pattern blocks shaping. Trousers construction, methods of trousers shaping by hands, body sizes schedule, manuals of 36 pattern cutting systems, and its sketches from nineteenth century have been analyzed. Then, by means of parameterization of historical pattern blocks, we have developed the universal trousers pattern cutting algorithm. The final step of the research has been devoted to virtual fitting technology that helps to determine the differences between historical trousers chosen as prototype and virtual image reconstructed by 3D CAD.

The authors have developed the parametrical module of 2D CAD and expanded the application of 3D CAD to re-designing of completely new object such as nineteenth century trousers pattern blocks in accordance with the historical method of shaping by hands. The conformity between the style of historical trousers and the virtual images reconstructed from two resources – pattern block and sketch silhouette – has been achieved.

This study demonstrated the contemporary approach to historical garments reconstruction by means of CAD. This study should help researchers of historical costume and practical specialists in apparel industry to apply historical heritage in a contemporary way.

Describes a PC‐based CAD system for producing made‐to‐measure garment patterns which has been developed and implemented in the commercial environment of a bridalwear manufacturer. The software simulates the hand drafting methods of the company while automating pattern production with the following benefits: first, very rapid production of made‐to measure patterns; second, production of patterns which require minimal alteration at first fitting; third, a user friendly interface with very short training period; fourth, the de‐skilling of the pattern cutting procedure so that problems of staff turnover and training are minimal; and fifth, the elimination of human error in pattern cutting. Initial software development concentrated on bodice patterns. Further enhancements included sleeves and skirts and the mixing and matching of these three components of a dress. Cutting layouts were produced using automatic layout algorithms so that the whole procedure from order and measurements entry through pattern drafting and lay‐planning to the final full scale plotting could be carried out automatically. Furthermore, a queuing system allowed several orders previously entered on the computer to be processed in succession without any intervention by an operator. All the company’s styles are now held by the computer, which is in constant use, to the exclusion of the previously used skilled and lengthy hand drafting methods.