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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.

This paper presents an experimental study on needle heating in sewing heavy materials such as upholstery fabrics. In the experiments, infrared (IR) radiometry, high speed line scanning IR radiometry, and high speed IR radiometry are used to obtain thermal images of the needle during sewing. In particular, IR radiometry was used in lower speed sewing (approximately 500rpm). High speed IR and high speed line scanning IR radiometry were used for medium speed sewing (1,000‐2,000rpm). Using Taguchi’s design of experiment method, the effects of various factors are studied including needle conditions (sharp or blunt), sewing speeds, number of stitches per inch, material being sewn, and thread tension. It is found that even with air vortex cooling the needle may still reach high enough temperatures that may affect the sewing quality and even cause thread breakage. This was confirmed via a thread tensile testing experiment. An empirical model of the mean needle temperature is also proposed and tested.

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.

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.

In the trend from mass production to mass customization, more flexible production systems are required. In the clothing field, many studies about automatization of sewing processes have been done into producing small amounts of various kinds of products. The purpose of this paper is to propose a versatile guiding mechanism of a cloth for an automatic sewing system.

Real sewing processes were referenced for the mechanism, and curved stitch is formed holding a point on a cloth. This mechanism consists of a solenoid for holding a cloth and a roller to prevent deformation of the cloth. When a cloth is sewn with the mechanism, the trajectory of the stitch is unstable because of anisotropy of a cloth. A precise trajectory was obtained by adding a device to control the pressure of the roller for holding a cloth and keeping a tension properly applied to a cloth.

It was found out that shearing property is the most related to the stability of sewing trajectory. If the tension for guidance applied to a cloth is constant, deformation of the cloth was observed and it was the cause of unstableness of sewing trajectory. By controlling the tension for guidance applied to a cloth properly according to the direction of the cloth, precise sewing trajectory was obtained.

There have been some studies in which sewing conditions were dynamically controlled according to the mechanical properties of a cloth. To these studies, here it was proposed that sewing conditions were kept constant by controlling the guidance of a cloth according to its mechanical properties.

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 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.

This paper aims to develop a single regression model (instead of developing models separately for each thread type) to predict the sewing thread consumption for cotton and polyester staple spun threads.

A single regression model is developed for predicting sewing thread consumption for cotton and polyester threads. The polyester sewing threads have lower sewing thread consumption as compared to cotton threads because of their higher elongation behaviour. The model differentiates between the cotton and polyester sewing threads using their elongation values at peak levels of tensions experienced by the sewing threads during stitch tightening. By comparing the estimated thread consumption values with actual values, the effectiveness of model is evaluated with root mean square error and coefficient of determination (R²).

During the sewing process, by understanding the behaviour of different types of sewing threads, it is possible to develop a single regression model for all types of threads.

The sewing thread consumption can be easily calculated for cotton and polyester sewing threads using a single regression equation using the sewing assembly thickness, stitch density and elongation of thread at peak tension. The garment manufacturers need not depend on different charts for sewing thread consumption for stock management.

The sewing thread consumption is different for different types of threads, and garment manufacturers have to depend on different charts given by sewing thread manufacturers or use different equations for each type of threads. Using this single regression equation, sewing thread consumption for cotton and polyester sewing thread can be estimated accurately.

Selection of suitable sewing needle is one of the most important parameters for ensuring an effective and fault‐free sewing process. This task requires good knowledge of basic characteristics of a sewing needle, i.e. needle type, point shape and needle fineness. Also good knowledge of sewing materials is required. The contribution presents an analysis of important parameters that influence the sewing needle selection in women’s underwear production. The importance of those parameters in ensuring the appropriate seam quality is described. The selection of a suitable sewing needle was carried out on the basis of analysis of influential sewing parameters with application of machine learning from examples.

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.