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Seam efficiency plays an important role for obtaining a desired seam quality. Therefore, this issue is often referred in research papers. The purpose of this paper is to determine the seam strength and efficiency as well as examining, if and how such factors as: a kind of fabric, kind of thread, kind of seam and the stitch density influence the transverse seam strength and the seam efficiency.

For research four types of polyester/wool fabrics having different structural parameters and two types of polyester sewing threads were used. Three types of seam were made. The fabric samples were sewn using lockstitch with three different stitch densities. Obtained in this way seams were tested on the tensile machine. The influence of individual factors on the seam strength and its efficiency was assessed statistically using a multivariate variance analysis (ANOVA).

The findings of this study revealed that the independent variable – stitch density affect significantly of the seam strength as well as its efficiency. Seam strength and seam efficiency values increase with the increase stitch density. Moreover, the variance analysis showed that a kind of fabric also is a statistically significant factor for the seam efficiency and its strength. Furthermore, in the case of seam efficiency it is also important to the stitch direction. However, the study did not show an impact of kind of thread and kind of seam on dependent variables: the seam strength and its efficiency.

Due to the fact that this paper focuses on the seams made only on wool/polyester fabrics with two the most popular weaves, involving only two sewing PES threads, the conclusions presented in this paper are valid only to this assortment and cannot be generalized.

So far, it has not been taken research on the effect of seams with the different number of sewn layers on the seam strength and efficiency. This issue has been taken in this work.

This paper aims to define the dominating factors having influence on the quality of the seam by sewing of fine fabrics and their optimum values.

Ten factors defining a seam's quality are chosen on the base of literary research. There was a check for concurrence of specialists' opinions, as the Spearman's coefficient of concordance was determined. A designed experiment with variation of the first three of the arranged factors was made. Mathematical models for the tensile and the aesthetical properties of the seam were devised, and also optimization made.

A classification of the properties, defining seam's quality, is made. A cause‐effect diagram of Ishikawa with aiming parameter – quality of the seam – has been developed. On the basis of a survey the factors that have a great deal of influence on it are presented. Mathematical models for seam's strength, elongation and smoothness are produced by changing the following factors: straining of the upper thread, size of the needle and load on the pressing foot are worked out. Received models are optimized.

The research was conducted using a sewing‐machine class 301. Received results and conclusions refer to seams made from base material – fabric from PES and sewing thread from 100 percent PE.

Optimum values have been established for the straining of the upper thread, the size of the needle and the load on the pressing foot by sewing of fabric from synthetic silk with mass applicable machines, needles, and sewing threads.

The research has been done in several directions: systemizing the seam's properties for evaluation of its quality and the factors defining it, inquiry into the significance of the different factors and implementation of a designed experiment. Consultations were made with a broad circle of specialists and these results are given in visual systems (schemes and graphs).

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.

Plans a wear simulation of assembled textile structures by sewing, basing the study on the submission of standardized seams carried out on 40 wool fabrics and blends containing wool to a series of 20 cycles of fatigue, including: washing, drying and submission to a static mechanical load under determined characteristics and steam ironing. Seams in the warp and weft directions were performed on. Examines the following parameters: fabric strength and elongation to break; seam strength and slippage; seam efficiency; seams’ opening limit and both the modulus at 1mm and at break, along the fatigue cycles. Analyses results obtained in function of the seam directions and fatigue cycles.

This paper aims to develop a method to extract the weld seam from the welding image.

The initial step is to set the window for the region of the weld seam. Filter and edge‐operator are then applied to acquire edges of images. Based on the prior knowledge about characteristics of the weld seam, a series of routines is proposed to recognize the seam edges and calculate the seam representation.

The proposed method can be used to extract seams of different deviations from noise‐polluted images efficiently. Besides, the method is low time‐consuming and quick enough for real time processing.

Weld seam extraction is the key problem in passive vision based seam tracking technology. The proposed method can extract the weld seam even when the image is noisy, and it is quick enough to be applied in seam tracking technology. The method is expected to improve seam tracking results.

A useful method is developed for weld seam extraction from the noise‐polluted image based on prior knowledge of weld seam. The method is robust and quick enough for real time processing.

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.

Seam pucker is one of the most important aspects of garment quality in the sewing process. Recently, automatic sewing systems have been developed and seam pucker or other defects would have to be automatically inspected in these systems. Two systems of automatic, contactless measurement of seam pucker have been developed. One of the measurement systems, with which surface shape of seam pucker was measured, is based on laser technology. Intensity of reflected ultrasonic wave is measured using another measurement system. The laser measurement system has been applied to moderate or severe seam pucker and the ultrasonic wave system has been applied to the accurate evaluation of very small seam pucker. The result of the evaluation by machine has to match the result of subjective evaluation by humans. To verify this, samples of seam pucker were evaluated using five judges. With the measurement data of surface shape of these samples, the power spectra of the wave form of seam pucker are calculated. Analyses and correlates the relationship between objective measurement and subjective evaluation by discriminant analysis, with the result of subjective evaluation and the power spectra of the samples. Having obtained these relationships, the degree of seam pucker can be measured objectively by both systems.

The weld seam detection is required for a welding robot to preplan the weld seam track before the actual welding. The purpose of this paper is to investigate this subject in natural lighting conditions.

This paper presents an efficient algorithm of weld seam detection for butt joint welding from a single image. The basic idea of the approach is to find a pair of weld seam edges in local area first. Then, starting from the two endpoints of each edge, search for the remnant edge by iterative edge detection and edge linking.

The proposed method is insensitive to the variance of the background image and can apply to most shapes of weld seams in butt joint welding.

The proposed method is designed only for butt joint welding, and it is performed before actual welding.

The system is applicable to preplan the weld trajectory for most shapes of weld seams in butt joint welding. In addition, the proposed technique may have some potential applications in the field of tailor‐welded blanks.

The proposed algorithm is based on local image processing and detects the whole weld seam from a single image without giving any initial seam, which is insensitive to the variance of the background image and has low‐computation cost.

Owing to a high amount of stress, seam failure in workwear fabrics makes the fabric unsuitable although the fabric strength is high. It is therefore important to predict the seam strength to ascertain the performance of the garments during use and determine the required thread strength and stitch density to match the required seam strength. In all of the earlier predictive equations, seam strength is predicted from thread strength and stitch density along with some multiplicative factors. During the sewing process, a substantial loss in needle thread strength occurs; therefore, the thread becomes weaker than expected after incorporation into the seam. In this paper, the effects of various machine and process parameters are studied on thread strength loss and seam strength. The seam strength is predicted from the loop strength after considering the loss in thread strength. It is observed that higher seam strengths are observed when stronger threads are used for sewing. Loss in thread strength has a significant influence on the seam strength. Seam strength can be predicted using stitch density and thread loop strength, by considering the loss in thread strength during the sewing process. A closer match between predicted and experimental seam strength is possible.

This paper reports an experimental investigation into the effect of laundering on seam tensile properties with the variation of stitch density, linear density of sewing threads and composition of base material. Tensile properties such as initial modulus, secant modulus, seam strength, strain at fracture and work up to fracture increase with stitch and linear density of sewing threads. The impact of coarser yarn is greater on seam properties of polyester‐cotton fabric than cotton fabric. The tensile properties except seam strain are reduced due to laundering. Reduction in initial modulus and secant modulus due to laundering is higher for polyester‐cotton fabric whereas decrease in seam strength, seam efficiency and strain at break is greater for coarser sewing thread.