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The apparel industry is a labor-intensive industry, which depends mainly on the performance of the worker. The purpose of this study is to present an ergonomic redesign of the sewing machine workstation, with different sewing table heights and inclination angles, based on the operator’s anthropometric data.

A flexible ergonomic sewing table has been designed, four main workstation-setting factors were studied; sewing desk inclination angles – X_1, height – X_2, sewing machine type – X_3 and operator’s body mass index (BMI) – X_4, with three levels for each factor, except sewing machine type, which only has two levels. The study was undertaken to specify the limitations and advantages of each combination tested. Different measurement techniques were used; subjective information, production rates – P, working postures (head, neck and trunk inclination angles in the kinematic stage) were measured.

Sewing operators’ sitting posture angles in the kinematic stage were affected more or less by their anthropometric measurements and the type of sewing machine. These two factors should be taken into consideration when ergonomically redesigning the sewing machine workstation.

A new ergonomically redesigned sewing machine table can be incorporated into garment factories, taking into consideration the BMI of the operators to improve their productivity and reduce musculoskeletal disorder complaints due to incorrect operators’ posture.

An important correlation was found between the sewing operator’s anthropometric body measurement – BMI and the type of sewing machine (with significant R^2 = 0.8385 and 0.9764 with both the head and neck inclination angles O_H, O_N, respectively).

Denim fabrics of various weight ranges were sewn with three different compositions of sewing threads ‐ 100 per cent cotton, 100 per cent polyester and corespun thread ‐ with all possible ticket numbers, to examine the interaction of various fabric‐thread combinations. The sewing thread performance in terms of seam efficiency, pucker, slippage and needle cutting index was determined and the results were analysed in the light of the dimensional and mechanical properties of the fabric, thread and seam itself. Corespun threads were found to be most suitable from a seam efficiency point of view. However, other sewing parameters such as pucker, slippage and damage were adversely affected by sewing with corespun threads. Tensile properties of fabrics and threads were found to be the most important factors for sewability. Breaking strength and elongation of the fabric and sewing thread had an excellent correlation with seam efficiency. Cotton threads were found to be most suitable for sewing denim from a seam puckering point of view. On the other hand, polyester threads were more prone to develop seam pucker. Corespun thread was the greatest yarn damager compared to cotton and polyester threads. Fabric cover factor and sewing thread diameter were highly correlated with the needle cutting index.

Presents some factors that influence the design of workplace and worker loading in the process of sewing garments. Researches both existent and suggested work methods in workplace design and worker’s loading, with regard to sewing men’s shirts. The use of the suggested working method enables minimization of measured working time of the analysed technological operation of 21.77 per cent. The estimation, by OVACO working postures analysing system, the OWAS method shows that worker’s loading for a newly designed workplace compared to the suggested working method brings, in principle, advantages for the workers.

To reduce the difficulty of the sewing process and promote the automation process of fabric sewing, a soft finger-assisted feeding method is proposed to investigate the effect of sewing process parameters on the quality of automatic sewing.

Taking cotton woven fabrics as an example, the causes of sewing deviation are firstly investigated from three aspects: fabric properties, sewing speed and sewing edge position. By simulating the sewing action of human hands, the method of reducing sewing deviation by using soft fingers to press and feed the fabric is proposed. Then, four sewing process factors, namely, robot arm end pressure, sewing machine speed, sewing needle gauge and stitch density, were selected, and three levels were set for each factor to design orthogonal sewing experiments. The sewing deviation of 1# sample under different sewing processes was measured, and the optimal parameter matching for automatic sewing of this specimen was derived.

The findings demonstrate that, while sewing cloth automatically, the sewing deviation is significantly influenced by the robotic arm's end pressure, sewing speed, and stitch density, whereas the sewing deviation is not significantly impacted by the needle number.

The findings offer fundamental information for the development of an automated sewing procedure using soft fingers, which has theoretical and real-world application value to speed up the intelligent modernization and transformation of the apparel industry.

Simulating the behavior of clothing has always been of interest in the apparel, fashion and computer game industries. With the development of these industries, there is a need to increase the accuracy of clothing simulation techniques. A garment contains many seams whose behavior affects its final appearance. In this study, a numerical model is presented to simulate seam puckers in single- and double-layer fabrics.

A yarn-level simulation technique has been used for this purpose. Based on this technique, the individual threads in the fabric structure and the sewing threads are modeled separately. Then, their behavior and interaction with each other are considered in the seam pucker model.

The model is used to simulate the real samples. The results show that the proposed model is able to simulate the degree of seam puckering for a single-layer fabric with an average error of 7.9% and for a double-layer fabric with an average error of 8.5%.

The behavior of the seam is affected by the properties, behavior and interaction of the sewing threads and yarns in the fabric structure. In previous studies, the parameters related to seams and fabrics were not fully considered. In this study, a new yarn-level model is presented to simulate seam puckering in woven fabrics. The most important advantage of this type of simulation is the ability to examine the interaction of fabric threads as well as the interaction of sewing threads with each other and with the threads of the fabric structure.

The garment factories focus on improving their production systems by involving innovative and advanced production methods and/or techniques to cope with fast-changing trends. Accordingly, this study aims to establish the standard allowed minutes (SAMs) and sewing efficiencies for Tanzania’s sewing industry, thus improving the production processes.

The research deployed a quantitative method. A stopwatch measured each operation for shirts and trousers to compute SAMs and efficiency. The shirt manufacturing processes involved 40 operations. Ten measurements were taken from different SL and LL industries operators for each operation. The trouser comprised 42 operations with 10 measurements taken from a different operator at the same garment factories for each operation.

SAMs for shirts at SL and LL factories were 29 and 31 min, respectively, while trousers were 30 and 34 min. The sewing efficiencies for shirts at both SL and LL factories were 83.98% and 81.93%, respectively. Similarly, the sewing efficiencies for trousers at both SL and LL factories were 81.25% and 80.95%, respectively.

Since SAMs results are not established through literature rather a quantitative approach, the findings thus place crucial information for similar factories to benchmark from. Such information are crucial as factories could increase productivity and operational efficiency, reduce costs and non-value adding activities and estimate lead times. Notwithstanding the findings gathered, the study only established SAMs for two garments.

Although the garment industry has been developing over the years, this study was probably among the first studies in Tanzania that established SAMs. Theoretical underpinnings indicate that the factories use the experience to assemble garments, thus the need for this study.

A study of thread tensions on a lockstitch sewing machine was made, measuring simultaneously both the needle and bobbin thread tensions. Experiments were carried out under specified sewing conditions, whereby needle and bobbin thread tensioner adjustment, sewing speed, number of plies, fabric quality and sewing thread quality were varied in order to investigate the effect of these factors on the needle and bobbin thread tensions. The patterns of the thread tension traces obtained were analysed as well as the effect of these factors on the peak tensions detected on both thread tension traces. Four significant peak tensions on the needle thread tension trace and two significant peak tensions on the bobbin thread tension trace were detected, during a stitch cycle. It was found that no significant variations occurred as far as the timing and shape of the peak tensions were concerned. However, variations were detected in the peak tensions according to the sewing conditions, as expected. From the analysis of the data obtained, multiple regression equations were derived to predict, with a good degree of accuracy, the peak tensions generated, according to the sewing conditions.

The mechanism of strength reduction of sewing threads has been discussed in Part I of this paper. The effect of fabric tightness and certain thread properties like its size, coefficient of yarn‐metal friction, twist direction, number of piles, type of fibre and fibre denier on strength reduction has been studied and found to influence the severity of strength reduction of the thread.

This research aims to develop design solutions for all the obstacles that workers face during the sewing process, and these solutions are focused on the following: chair design, sewing table design and sewing machine pedal. The design of the workplace includes the order of the components of the work according to the ability of the human body to handle lighting, ventilation and noise. Both the university and research centre consider that the purpose of the research is to examine these obstacles and propose appropriate solutions that could eliminate these occupational diseases that result from the process of sewing, and increase the production rates and quality which will consequently stimulate the Egyptian economy.

The research originates from the work of an integrated regulatory framework of design tools and equipment used for the sewing process and the related work place in accordance with design ergonomic objectives that when achieved, will accelerate the performance and quality of production, and prevent occupational diseases resultant from poor design. The research has also developed a set of recommendations that deal with the deficiencies in the performance of the sewing process, in order to raise the competitiveness of the garment industry in Egypt.

Evaluates the mechanical properties of 60 different shirting materials: fabric extensibility, formability, shear rigidity, bending rigidity, relaxation shrinkage, and hygral expansion by the adoption of the fabric assurance by simple testing (FAST) system. Investigates manufacturing processes comprising spreading, cutting, sewing, handling, pressing and packaging and correlates the measured properties of the shirting fabric with their actual performance during making up. Claims this overall evaluation of respective fabric performance enables manufacturers to identify the range of mechanical properties ideal for high‐quality shirt production. Adds that specific manufacturing instructions can be prepared, based on the results of fabric property evaluation, for fabrics which tend to present difficulties in production. Points out that these can considerably expedite the manufacture of garments, avoiding the alternative – expensive “trial and error” – solution to problems.