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Article
Publication date: 1 May 1995

Darja Zunic Lojen

Presents the influence of seam length, normal stitching velocity of a sewing machine and a working method on stitching velocity of sewing. Results show that better stitching…

199

Abstract

Presents the influence of seam length, normal stitching velocity of a sewing machine and a working method on stitching velocity of sewing. Results show that better stitching velocities of sewing are gained by longer length of seams and higher than normal stitching velocities of a sewing machine. Reveals the working method and type of feeding of material affect the achievement of higher stitching velocities.

Details

International Journal of Clothing Science and Technology, vol. 7 no. 2/3
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 2 November 2015

Ge Qiang, Zheng Shanshan, Zhao Yang and Chen Mao

This paper aims to propose image stitching by reduction of full line and taking line image as registration image to solve the problem of automatic optic inspection in PCB…

Abstract

Purpose

This paper aims to propose image stitching by reduction of full line and taking line image as registration image to solve the problem of automatic optic inspection in PCB detection. In addition, surf registration was introduced for image stitching to improve the accuracy and speed of stitching.

Design/methodology/approach

First, image stitching proceeded by method of full line reduction and taking line image as registration image; second, surf registration was introduced based on the traditional PCB image stitching algorithm. Scale space of the image pyramid was adopted for confirming relative future points between stitching image. The registration means of nearest neighbourhood and next neatest neighborhood was selected for feature matching and fused in region of interest to fulfil image stitching.

Findings

The improved stitching algorithm with small data size of image, high speed and noncumulative transitive error eliminated displacement deviation and solved the stitching gap caused by uneven illumination, to greatly improve the accuracy and speed of stitching.

Research limitations/implications

The research of this paper can only used for appearance detection and cannot be used for solder joint inspection with circuit detection or invisible solder joint detection; it can identify and mark PCB component defects but cannot classify automatically, thus artificial confirmation and processing is needed.

Originality/value

Based on the traditional image stitching means, this paper proposed full line reduction for image stitching, which reduces processing of data and speeds up image stitching; in addition, surf registration was introduced into the study of PCB stitching algorithm, which greatly improves the accuracy and speed of stitching and solves stitching gap formed by opposite variation trend of image local edge caused by uneven illumination.

Details

Circuit World, vol. 41 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 9 March 2021

Qin Qin, Jigang Huang, Jin Yao and Wenxiang Gao

Scanning projection-based stereolithography (SPSL) is a powerful technology for additive manufacturing with high resolution as well as large building area. However, the surface…

Abstract

Purpose

Scanning projection-based stereolithography (SPSL) is a powerful technology for additive manufacturing with high resolution as well as large building area. However, the surface quality of stitching boundary in an SPSL system has been rarely studied, and no positive settlement was proposed to address the poor stitching quality. This paper aims to propose an approach of multi-pass scanning and a compensation algorithm for multi-pass scanning process to address the issue of poor stitching quality in SPSL systems.

Design/methodology/approach

The process of multi-pass scanning is realized by scanning regions repeatedly, and the regions can be cured simultaneously because of the very short repeat exposure time and very fast scanning. Then, the poor stitching quality caused by the non-simultaneous curing can be eliminated. Also, a compensation algorithm is designed for multi-pass scanning to reduce the stitching errors. The validity of multi-pass scanning is verified by curing depth test, while the performance of multi-pass scanning as well as proposed compensation algorithm is demonstrated by comparing with that of a previous SPSL system.

Findings

The results lead to a conclusion that multi-pass scanning with its compensation algorithm is an effective approach to improve the stitching quality of an SPSL system.

Practical implications

This study can provide advice for researchers to achieve the satisfactory surface finish with SPSL technology.

Originality/value

The authors proposed a process of multi-pass scanning as well as a compensation algorithm for SPSL additive manufacturing (system to improve the stitching quality, which has rarely been studied in previous work.

Details

Rapid Prototyping Journal, vol. 27 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 4 May 2020

Guangzhou Zhu and Wenfang Song

The paper presents a method for the patterns simulation in the 3D virtual stitching and try-on system.

263

Abstract

Purpose

The paper presents a method for the patterns simulation in the 3D virtual stitching and try-on system.

Design/methodology/approach

First, the patterns are designed using the garment CAD software and stored in the DXF format. Second, the regular grid method is employed to mesh the patterns to be quadrangular, and the patterns triangular meshing can be obtained by connecting the diagonal of the quadrangular. Then a mass-spring model is established, and the forces analysis and the explicit Euler integration method are employed to accomplish the patterns simulation. The paper demonstrates the robustness of our simulation through two sets of experiments, including a lady’s dress patterns meshing experiments and the experiments of the virtual stitching of the lady’s dress.

Findings

The patterns meshing algorithm can meet the requirements of the internal meshing and the boundary meshing, and it is very important to select an appropriate meshing density. The implementation of the virtual stitching of the lady’s dress proves the effectiveness and usability of the simulation methods.

Research limitations/implications

The lady’s dress used in the experiments is a relatively simple fashion style, with only the front and back pattern. It is very worthy of further research on the effectiveness of the complex structure of clothing.

Practical implications

The paper includes practical implications of the methods of the patterns meshing and the virtual stitching of the simple fashion styles.

Originality/value

The simulation system is developed using VC++ 2015 with the help of the OpenGL functions library, which is proved as a simple, lower computation and robustness for the patterns simulation of the simple garments.

Details

International Journal of Clothing Science and Technology, vol. 32 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 February 1993

N. Dunning, C. Preece, K.S.H. Sadek, J. Grantham, S. Owen, G.E. Taylor, J.E.L Simmons and D.C. Reedman

In recent years NC controlled lock‐stitch sewing machines operating on shoe upper sub‐assemblies held in flat pallets have become well‐established in shoemaking businesses…

Abstract

In recent years NC controlled lock‐stitch sewing machines operating on shoe upper sub‐assemblies held in flat pallets have become well‐established in shoemaking businesses. However, a major problem for manufacturers of high‐quality footwear is that such machines are subject to malformation of the lockstitch when the pallet moves in certain directions with respect to the sewing head. The stitch malformation, known as half‐hitching, results in seams which have an inconsistent and unsightly appearance. Examines the reasons for half‐hitching and strategies for its prevention. One approach involves rotating the stitching head about a vertical axis so that the direction of sewing is always maintained at a tangent to the seam. Systems such as this have been proposed in the past but have been prohibitively complicated and cumbersome. Introduces a stitching machine concept which enables a much simpler demonstration rotating head stitching machine to be built. It is expected that industrially‐developed units using the principle illustrated will find widespread use in the shoemaking industry. They will be relevant not only in conventional pallet loaded NC stitching machines, but also in a new generation of palletless machines.

Details

International Journal of Clothing Science and Technology, vol. 5 no. 2
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 25 November 2013

Yanming Fan and Ming Li

The purpose of this paper is to present weighted Euclidean distance for measuring whether the fitting of projective transformation matrix is more reliable in feature-based image…

Abstract

Purpose

The purpose of this paper is to present weighted Euclidean distance for measuring whether the fitting of projective transformation matrix is more reliable in feature-based image stitching.

Design/methodology/approach

The hybrid model of weighted Euclidean distance criterion and intelligent chaotic genetic algorithm (CGA) is established to achieve a more accurate matrix in image stitching. Feature-based image stitching is used in this paper for it can handle non-affine situations. Scale invariant feature transform is applied to extract the key points, and the false points are excluded using random sampling consistency (RANSAC) algorithm.

Findings

This work improved GA by combination with chaos's ergodicity, so that it can be applied to search a better solution on the basis of the matrix solved by Levenberg-Marquardt. The addition of an external loop in RANSAC can help obtain more accurate matrix with large probability. Series of experimental results are presented to demonstrate the feasibility and effectiveness of the proposed approaches.

Practical implications

The modified feature-based method proposed in this paper can be easily applied to practice and can obtain a better image stitching performance with a good robustness.

Originality/value

A hybrid model of weighted Euclidean distance criterion and CGA is proposed for optimization of projective transformation matrix in image stitching. The authors introduce chaos theory into GA to modify its search strategy.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 6 no. 4
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 1 June 2005

Dubravko Rogale, Igor Petrunić, Zvonko Dragčević and Snježana Firšt Rogale

The equipment for computerised measuring of electrical power and energy is presented, adapted to the needs of investigating processing parameters of garment sewing operations.

Abstract

Purpose

The equipment for computerised measuring of electrical power and energy is presented, adapted to the needs of investigating processing parameters of garment sewing operations.

Design/methodology/approach

The method of measuring the energy necessary to run the sewing‐machine driving electrical motor is also presented, correlated to the stitching speed in joining a straight seam in a single, two, or three, segments. Electrical energy consumption is analysed as dependent on the stitching speed, varying the number of stitches in the seam.

Findings

The investigations described have shown the impact of the method of work applied and the effect of the changes in garment sewing operation in processing parameters on the level of electrical energy consumed by the sewing‐machine drive electrical motor. A new measuring method has been introduced in garment engineering, aimed at predicting electrical energy consumption in garment sewing operations, thus opening a completely new field of investigation in the area of garment technologies.

Originality/value

A method of calculating the energy processing parameters of sewing operations.

Details

International Journal of Clothing Science and Technology, vol. 17 no. 3/4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 12 December 2018

Muhammad Babar Ramzan, Abher Rasheed, Zulfiqar Ali, Sheraz Ahmad, Muhammad Salman Naeem and Ali Afzal

In the field of knitwear, dimensional stability is assumed as a critical problem that affects the quality and salability of a product. Although much work has been done in this…

Abstract

Purpose

In the field of knitwear, dimensional stability is assumed as a critical problem that affects the quality and salability of a product. Although much work has been done in this area with a focus on the factors affecting fabric shrinkage, however, there is a lack of work on knitwears with respect to their dimensional stability. The purpose of this paper is to investigate the impact of stitching parameters and wash types on the dimensional properties of knitwear.

Design/methodology/approach

The crew-neck t-shirts were prepared by using pique knitted fabrics. Different sewing and finishing parameters were used that include stitch density, stitch type, stitching thread and wash type. The critical measurements of the selected garment are taken as output variables which are body width, sleeve length, body length and across shoulder. After laundering process, shrinkage percentage was calculated by using before-wash and after-wash measurements.

Findings

This study shows that the stitching parameters affect significantly on knitwear’s shrinkage. Thus, when patterns are being developed for the cutting of fabric, expected shrinkage, known as residual shrinkage, must be considered to avoid unexpected changes in garment shape.

Originality/value

This research will be useful for knitwear manufacturing industry.

Details

International Journal of Clothing Science and Technology, vol. 31 no. 2
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 June 2001

Dubravko Rogale, Zvonko Dragčevic´ and Anica Hursa

An investigation is presented of the impact of mechanical auxiliary devices on sewing‐machines upon the processing parameters of sewing operations. Processing parameters are…

Abstract

An investigation is presented of the impact of mechanical auxiliary devices on sewing‐machines upon the processing parameters of sewing operations. Processing parameters are investigated at an ergonomically designed workplace, on a modern sewing‐machine, equipped with a processing microcomputer. Measuring samples are 300 to 1,000mm long, and stitching speeds are pre‐programmed – 1,500 to 4,700rpm. Values for sewing operation processing parameters are measured and stored using the measuring system for processing parameters MMPP, developed especially for the purpose of research in the field of garment engineering. The results obtained indicate that using a tape piper the basic time needed to perform the sewing operation is reduced by up to 61.2 per cent, while the use of a hemmer reduces it by 38.3 per cent. Specific time for sewing 1m of seam is reduced using the above auxiliary devices as follows: by 64.5 per cent using a tape piper and by 41.8 per cent using a hemmer. The degree of sewing‐machine utilisation is increased by 110.6 per cent using a tape piper, and by 59.8 per cent using a hemmer. Average stitching in machine‐hand sub‐operations is increased with a tape piper from 1,041 to 3,914rpm, and from 1,176 to 3,959rpm with a hemmer. The operation structure is altered by using auxiliary devices, achieving rationalisation of the movements constituting auxiliary‐hand sub‐operations, which has a considerable impact on the processing parameters involved.

Details

International Journal of Clothing Science and Technology, vol. 13 no. 3/4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 September 2005

Seungryeol Yoo and Daniel Walczyk

To provide an advanced cutting trajectory algorithm for the profiled edge laminae (PEL) rapid tooling (RT) process, which is ideally suited for large‐scale dies and molds. The…

1094

Abstract

Purpose

To provide an advanced cutting trajectory algorithm for the profiled edge laminae (PEL) rapid tooling (RT) process, which is ideally suited for large‐scale dies and molds. The process involves assembling an array of laminae whose top edges are simultaneously profiled and beveled using a line‐of‐sight cutting method based on a CAD model of the intended tool surface.

Design/methodology/approach

The cutting profiles for an individual tool lamina are based on intersection curves obtained directly from the CAD model, and generated with exact geometrical accuracy. Two adjacent slice profiles, which define a lamination's top edge and are represented as polylines, are stitched together using an adaptive surface reconstruction algorithm. A cutting trajectory algorithm then develops a series of suitable cutting vectors (i.e. position and cutting direction) that minimize abrasive waterjet (AWJ) cutting errors due to non‐uniform motion and variations in kerf geometry resulting from process parameter variations. The proposed cutting trajectory generation process is demonstrated virtually for an actual production tool.

Findings

The proposed algorithm yields well‐behaved AWJ cutting trajectories for individual lamina used in a PEL tool that are better than those obtained using any other algorithm found in the literature.

Research limitations/implications

The algorithm is intended for use with AWJ cutting of PEL tool surfaces. Suggested future research includes assessment of the algorithm for other lamina cutting methods including laser cutting and wire‐type electro‐discharge machining, extending the algorithm to handle conformal cooling/heating channels and internal cavities, and application of the algorithm to several industrial tool case studies.

Practical implications

The algorithm generates cutting trajectories directly from CAD geometry that are ideal for AWJ cutting of profiled edge lamina. It will simply make industrial implementation of the PEL RT process easier.

Originality/value

This paper provides a new cutting trajectory algorithm for the PEL RT process that is a significant improvement over comparable algorithms proposed in the literature.

Details

Rapid Prototyping Journal, vol. 11 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

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