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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.

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.

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.

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.

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.

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.

Pilling and abrasion resistance are two of the most important mechanical properties of the fabric that influence the appearance and performance of the fabric, particularly in the case of knitted fabrics. Since, these fabric features are affected by fabric structure the aim of present research is to investigate how utilizing miss stitches and tuck stitches in the fabric structure for design purposes will influence the pilling and abrasion resistance of interlock weft-knitted fabrics.

In this research, interlock fabrics with different number of miss or tuck stitches on successive Wales were produced and pilling performance and abrasion resistance of the fabrics were investigated.

The results revealed that increasing the number of miss/tuck stitches on successive Wales decreases the abrasion resistance and enhances the pilling tendency of the fabric. The presence of miss/tuck stitches on both sides of the fabric improves the abrasion resistance and pilling performance of the fabric compared to fabrics containing these stitches on one side of the fabric. Furthermore, the fabric resistance against abrasion and pilling is higher in fabrics consisting of miss stitches compared to fabrics consisting of tuck stitches.

The use of tuck and miss stitches in designing the weft-knitted fabrics is a common method for producing fabrics with variety of knit patterns. Since pilling and abrasion resistance of the fabric influence on its appearance and performance, and none of the previous research studied the pilling and abrasion resistance of interlock-knitted fabrics from the point of presence of tuck and miss stitches on successive Wales of the fabric, this subject has been surveyed in the present research.

The purpose of this study is to explore the effect of stitch type and stitch direction on the dynamic drape behavior of the woven fabric.

In this paper, the effectiveness of stitch type and stitch directions on dynamic drape behaviors were investigated. Fabric parts were sewn together with two types of the stitch (lockstitch and overlock stitch) on three different stitch directions (warp, weft and bias (45°)). The static drape coefficients (SDC) of unsewn and sewn fabrics were measured according to the image process method. Dynamic drape coefficients (DDC) of fabrics were also measured using the same method at six different (25, 50, 75, 100, 125, 150 rpms) rotation speeds. Additionally, bending length and bending rigidity were measured using the Cantilever test method.

Experimental results showed that stitch type and stitch directions are effective on the dynamic drape behaviors of the fabric. Overlock stitch resulted in greater DDC than the lock stitch. For both of the stitch type, DDC for the stitch on the warp direction are greater than the stitch on the weft and bias direction for all speeds. In addition, bending length, hence the bending rigidity, are greater for overlock stitch type and always weft direction resulted in greater than the warp and bias direction.

Fabric drape is vital for garment appearance and is gaining popularity with the advancement of virtual technology, enabling virtual visualization of garments. While previous studies have predominantly examined either the static or dynamic drape behavior of individual fabric panels, or solely focused on the static drape behavior of sewn fabrics, this study acknowledges the significance of incorporating the influence of stitch type and direction on dynamic drape behaviors. Considering that fabrics are sewn together to create garments and that DDC provides a more accurate representation of real-time fabric behavior compared to SDC, this research makes a valuable contribution to the existing literature by investigating the impact of stitch type and direction specifically on DDC.

This study aims to investigate the effects of the number of miss stitches and tuck stitches in the knit structure on the technological parameters and physical and mechanical properties of knitted fabrics.

The number of miss stitches and tuck stitches was increased from 3.6% to 8.3%, and the influence of this increase on knitwear properties was analyzed.

It was found that an increase from 3.6% to 8.3% leads to a decrease in the stretchability of knitwear in width from 330% to 290% and in length from 112% to 95%. With an increase from 5% to 6.3%, the surface density of knitwear decreases by 11.6 g. And with an increase from 6.3% to 8.3%, the surface density of knitwear decreases by 11.8 g. It was also found that the presence of miss stitches and tuck stitches in the knit structure reduces the material consumption, and the presence of miss stitches increases the shape stability of the knitted fabric.

It was concluded that the number of miss stitches and tuck stitches has the strongest influence on surface density, followed by volume density.

This paper aims to propose the artificial neural network (ANN) and regression models for the estimation of the thread consumption at multilayered seam assembly stitched with lock stitch 301.

In the present study, the generalized regression and neural network models are developed by considering the fabric types: woven, nonwoven and multilayer combination thereof, with basic sewing parameters: sewing thread linear density, stitch density, needle count and fabric assembly thickness. The network with feed-forward backpropagation is considered to build the ANN, and the training function trainlm of MATLAB software is used to adjust weight and basic values according to the optimization of Levenberg Marquardt. The performance of networks measured in terms of the mean squared error and the layer output is set according to the sigmoid transfer function.

The proposed ANN and regression model are able to predict the thread consumption with more accuracy for multilayered seam assembly. The predictability of thread consumption from available geometrical models, regression models and industrial empirical techniques are compared with proposed linear regression, quadratic regression and neural network models. The proposed quadratic regression model showed a good correlation with practical thread consumption value and more accuracy in prediction with an overall 4.3% error, as compared to other techniques for given multilayer substrates. Further, the developed ANN network showed good accuracy in the prediction of thread consumption.

The estimation of thread consumed while stitching is the prerequisite of the garment industry for inventory management especially with the introduction of the costly high-performance sewing thread. In practice, different types of fabrics are stitched at multilayer combinations at different locations of the stitched product. The ANN and regression models are developed for multilayered seam assembly of woven and nonwoven fabric blend composition for better prediction of thread consumption.

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.

The purpose of this paper is to measure the thermal and moisture resistance of the knitted upper fabrics with the foot model, which provided basis for designing and producing sports shoes with thermal-moisture comfort.

In this paper, different yarn materials and fabric stitches were selected as the changing factors. The three kinds of yarn materials and the three kinds of fabric stitches were combined to design and weave eight pieces of knitted upper fabrics. Human sweating was simulated by the thermal-moisture comfort foot model, and then tested the thermal and moisture resistance of eight pieces of fabrics in different parts of the foot. Finally, the relationship between yarn material, fabric stitch, and the thermal and moisture resistance in different parts of the foot was analyzed by data.

The composition of the yarn material and fabric stitch has certain effect on the thermal-moisture comfort in different sections of the foot. When the yarn material of the four parts of the lateral arch, medial arch, ankle and heel is composed of 31.1tex moisture wicking polyester/33.3tex spandex coated yarn, the yarn material of the instep and toes is composed of 31.1tex ordinary polyester/33.3tex spandex coated yarn, and all parts of fabric stitch choose single-sided loop transfer stitch, the knitted sports shoes have the best thermal-moisture comfort.

The study used the thermal-moisture comfort foot model to simulate the human body metabolism and sweating system. Through the quantitative analyze of the thermal and moisture resistance of knitted upper fabrics to provide basis for the producers to design and product knitted sports shoes with good thermal-moisture comfort.

Sewing is the most widely used and preferred method for manufacturing clothing products for extreme weather conditions and other industrial insulation systems. Multiple layers of functional fabrics in combination with insulation materials are used to thermally insulate precious body heat from its surrounding cold environment. The sewing process fixes the insulation material between the fabric layers. During conventional sewing, the insulation material is compressed along the stitch line. With the compression of the insulation material, entrapped air is forced to leave the insulation material internal structure, and heat loss occurs along the entire length of the stitch line. It results in the deterioration of thermal properties of the end product along the stitch line.

The amount of air, which is a decisive factor for thermal properties of any insulation system, was investigated at the level of a unit stitch length of a lockstitch. Conventional microscopy methods are not suitable to study the compression along the stitch line. With the help of X-ray tomography, the three-dimensional data of a stitch was taken and studied to measure the volume of air. The samples were prepared with conventional lockstitch sewing and a newly developed innovative sewing method “Spacer Stitching.” The results are compared with each other in terms of the amount of air present in a unit stitch length.

Calculations based on X-ray tomography images of lockstitch and spacer stitch revealed that, in the case of lockstitch, a unit stitch has a 15% of its volume made up of material and 85% of its volume by air. In comparison, the spacer stitch with the same sewing and fabric parameters has a material volume of 4.6 % and an air volume of 95.4% in a single stitch.

The research can positively improve the thermal properties of sewn material made for insulating purposes of conventional clothing as well as of industrial insulations.

There is no literature available which investigates and calculates the amount of air and material present along with a stitch line.

The purpose of this paper is to develop a user friendly, wearable pain management system by optimizing CAD embroidery parameters for manufacturing high performance dry transcutaneous electrical neural stimulation (TENS) electrodes.

User-centered design methodology is employed to identify user needs related to TENS devices. Optimization of CAD embroidery parameters was done by measuring and calculating resistance and signal-to-noise values for electrodes manufactured with different conductive thread, stitch pattern, and stitch density types.

Characteristics of the conductive thread such as thickness and irregularity, embroidery stitch pattern, stitch density therefore the amount of conductive thread used all effect resistance values and signal-to-noise values of TENS electrodes. Low resistance of TENS electrode surface does not mean high signal-to-noise ratio and high TENS signal quality. Satin stitch type with low stitch density provides the best resistance and signal-to-noise ratio for a TENS electrode.

This study reported the design process of a wearable pain management system with a focus on optimization of embroidery manufacturing parameters for development of TENS electrodes. The design process not only required technical optimization but also understanding user problems related to use of conventional TENS devices. Proposed end product is a user friendly, electronic textile based, wireless wearable pain management system in different forms suitable for major pain areas such as knee, elbow and neck.