Search results

Quantitative fabric‐needle‐sewing machine interactions at different speeds have been used to construct qualitative rules mapping fabric properties to optimum sewing machine settings for the next generation of “intelligent sewing machines”, using model free estimation. The inference procedures of fuzzy logic have been implemented in a neural network to allow for optimization of output membership functions and subsequently, self‐learning. The technique is successfully applied to industrial lockstitch and overlock sewing machines. Optimum settings were achieved under static and dynamic machine conditions from the properties of difficult fabrics and compensation for mishandling by the operator over the speed range of the sewing machine.

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).

The purpose of this review paper is to define the dominating factors (such as fiber, yarn, fabric structure, sewing thread, sewing needle and machine parameters) that affect the seam damages and causing defects. It also describes the various explanations of sewing defects in garment production and critically analyzes them for optimum selection of parameters and speeds for minimizing such faults. Hence, the knowledge of various factors which affect the sewing damages/defects will be helpful for garment manufacturers/researchers to know influence of the parameters and control the quality of producing seam.

This section is not applicable for a review paper.

Sewing damages such as needle cut and other sewing damages/defects are studied mostly in woven fabric. There are very few studies conducted on knitted fabric sewing damages/defects. The sewing damage problems do not have single solution that is capable of removing these damages in fabric. All the determined and affecting parameters related to fiber, yarn, fabric construction, sewing thread and sewing machine must be examined to design appropriate remedial measurement related to machine design, fabric parameters and sewing thread. This could help in minimizing or eliminating the needle cut and other sewing damage problems.

It is an original review work and is helpful for garment manufacturers/researchers to reduce the defects and be able to produce good quality seam.

In this paper, the contribution of dynamic loading, needle and fabric, and the bobbin thread interaction on the changes in the tensile properties of the needle thread are to be investigated.

Tensile properties of the needle thread have been studied at four sewing stages, namely before being subjected to any loading, after dynamic loading, before bobbin thread interaction and after sewing.

It is observed that bobbin thread interaction plays a dominant role in the reduction of tensile properties except breaking elongation in cotton threads. Dynamic loading is mainly responsible for reduction in the breaking elongation of cotton threads. During sewing, there is an increase in initial modulus due to the dynamic loading, which is more in the case of cotton threads than polyester threads. However, the impact of dynamic loading on tenacity, breaking elongation and breaking energy is greater for coarser cotton thread. The contribution of bobbin thread interaction is more for fine threads as compared to coarse threads.

Since seam strength is dependent on the thread strength, a reduction in thread strength during sewing will lead to lower seam strength than expected. Therefore, in order to minimize the thread strength reduction, it is important to understand the contribution of different machine elements or processes during sewing. During high‐speed sewing, the dynamic and thermal loading are found to be the major causes of strength reduction of needle thread, which can go up to 30‐40 per cent. However, the extent of strength loss at different sewing stages is unknown.

The study will help in engineering sewing threads, designing of sewing machines and selection of process parameters for controlling loss of useful properties of sewing threads.

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

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.

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.

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

In accordance with his/her psycho‐physical abilities and degree of skill, regulating system in the operator's brain will match the speed of sewing operations, e.g. actual machine stitching speed, using a simple movement of the foot, to adapt it to his/her sensory and motoric reaction abilities. Workpiece in sewing is fed employing three degrees of freedom movement, i.e. using three independent regulating circuits: position of the seam, edges and workpiece layer length. Cybernetic bases of the regulating system man‐machine‐workpiece are presented, as well as the development of the necessary and maximum possible sewing machine operator's reactions in joining curved seams. The procedure is explained by constructing a mathematical model and obtaining the equations used in calculating necessary and maximum operator's reaction abilities. Measurements necessary were performed in the Department of Clothing Technology, Faculty of Textile Technology, University of Zagreb, using modern measuring equipment while garment‐sewing processes were recorded under actual in‐plant conditions. The results obtained were computer‐processed and a 3D graphic representation was obtained together with a mathematical model appropriate to calculate interdependence of the mentioned parameters. Appropriate software package was developed, which allows a quick, accurate and continuous determination of normal machine‐hand times, as dependent on all the influential parameters.

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.

The aim of the present study is to consider the influence of the tensile behavior of fabric and sewing thread on the seam appearance.

In this study, the formation of seam puckering on two elastic and normal woven fabrics was explored. In order to prepare samples, various sewing threads were applied. Test specimens were sewn under five different thread tension levels. Then the appearance of samples was evaluated subjectively to determine their seam puckering grade before and after the laundering process.

The obtained outcomes of this study present that although sewing thread tension increment decreases the seam pucker ranking in the similar sewing condition, elastic fabrics have a greater seam pucker grade compared to the normal fabric due to the fabric extension and contraction during sewing and after sewing process, respectively. In addition, the elastic strain of the sewing thread is the key factor that determined sewing thread's tendency to make seam puckering. Moreover, the laundry process due to the relaxation of the sewing thread decreases the seam pucker grade.

The consistency of the tensile property of fabric and sewing thread is a crucial parameter in improving the seam appearance and obtaining a smooth seam.

Reports research into developing the ability to sense characteristic information about fabric/machine interactions for real‐time control of the industrial sewing process. The sewing system under investigation was equipped with displacement and force transducers to measure the dynamic response of the feeding system during various modes of operation. A combination of fabric and machine factors was considered in a one‐half fractional factorial experimental design, including: fabric type, number of fabric plies, presser foot type, presser foot preload, and machine speed.

Despite the globalization and internalization of competition and surplus of apparel production, high labour costs and other economic pressures, apparel products are still being produced using traditional methods and machinery, the mechanics of which have not fundamentally changed since the seventeenth century, even nowadays when the materials produced are very flexible and diverse in texture and properties. In developing the industry further, the nature of interaction between machinery, fabric and operatives has to be taken into account, and this poses some real problems if one has to put forward realistic solutions for future industrial development. It is therefore important to be able to take into consideration fabric/machine/human interactions during the manufacturing process in order to propose the next generation of manufacturing systems which is much needed in the current apparel industry. Reports on findings in the area of intelligent garment manufacture which is a means of introducing flexibility, quality, production efficiency and maximization of resources to the apparel industry. Primarily emphasizes the importance of fabric properties and their interaction with the whole manufacturing process, the labour force and especially with sewing. In order to achieve this, applies computational intelligence and engineering to research, develop and implement intelligent textile and apparel environments, and introduce desired flexibility into the whole area of textile and apparel processes, especially in terms of quick response (QR) and just in time (JIT).