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Sewing is one of the most important processes in the apparel industry for the production of high-quality garments. Although some research and improvements have been carried out in this area, the sewing process has remained almost unchanged throughout the years, staying largely dependent on the operator skills to set up sewing parameters and to hand...
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We consider a system of multiple insulating rigid bodies moving inside of an electrically conducting compressible fluid. In this system we take into account the interaction of the fluid with the bodies as well as with the electromagnetic fields trespassing both the fluid and the solids. The main result of this article yields the existence of weak s...
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... It can rightly be considered a universal tool for investigating processing parameters in real in-plant conditions, and, as such, a necessary tool for clothing engineering [5]. Silva et al. have studied the compression force and the displacement waveforms from the presser foot bar, as well as the admissible displacement limits used to monitor (on-and offline) fabrics' feeding efficiency [6]. Rogale et al. studied the energy consumption of sewing machines in 2005. ...
The clothing industry due to the rapid changes in the technological and economical fields faces continuously new challenges like efficient machine and process settings’ changes for individual production orders for smaller quantities; increased product and materials variety and increased competitiveness through higher quality and lower production costs. Energy consumption is very important because, besides the varying costs (material, labour), the costs of energy are one of the key factors affecting the manufacturing costs, which is the main factor affecting the final price of the clothing products. It is well known that energy costs constitute 10–15 % of the overall manufacturing costs in the apparel industry. In the present study, the correlation of the various sewing parameters with the energy consumption and thus the energy costs are examined. In order to obtain this goal, a data collection system has been designed in order to meet the needs and the nature of the measurements. Sewing experiments were carried out on different samples using various sewing parameters and the consumption of the electrical power was monitored. Additionally, the measurements obtained during the experiments were sent and stored in a computer for the processing of the signals and their statistical evaluation.
... It can rightly be considered a universal tool for investigating processing parameters in real in-plant conditions, and, as such, a necessary tool for clothing engineering [5]. Silva et al. have studied the compression force and the displacement waveforms from the presser foot bar, as well as the admissible displacement limits used to monitor (on-and offline) fabrics' feeding efficiency [6]. Rogale et al. studied the energy consumption of sewing machines in 2005. ...
The clothing industry due to the rapid changes in the technological and economical fields faces continuously new challenges like efficient machine and process settings’ changes for individual production orders for smaller quantities; increased product and materials variety and increased competitiveness through higher quality and lower production costs. Energy consumption is very important because, besides the varying costs (material, labour), the costs of energy are one of the key factors affecting the manufacturing costs, which is the main factor affecting the final price of the clothing products. It is well known that energy costs constitute 10–15 % of the overall manufacturing costs in the apparel industry. In the present study, the correlation of the various sewing parameters with the energy consumption and thus the energy costs are examined. In order to obtain this goal, a data collection system has been designed in order to meet the needs and the nature of the measurements. Sewing experiments were carried out on different samples using various sewing parameters and the consumption of the electrical power was monitored. Additionally, the measurements obtained during the experiments were sent and stored in a computer for the processing of the signals and their statistical evaluation.
... Sewing is one of the most critical operations in garment production [1,2]. Industrial sewing operations are usually carried out by using industrial sewing machines. ...
Sewing is a critical operation in garment production process. Therefore, alternative sewing machines must carefully be evaluated prior to procurement. Multiple criteria decision making (MCDM) techniques can effectively be used in sewing machine evaluation process since multiple evaluation criteria including speed and price must be considered. However, physically meaningless subjective weights are assigned to evaluation criteria in most MCDM techniques. Linear Physical Programming (LPP) is a MCDM methodology that eliminates this subjective weight assignment process by allowing decision makers to express their preferences in a physically meaningful way. In this study, a sewing machine selection problem faced by a textile company is solved using LPP.
... At present, there are few researches on EMS fabrics with seaming stitch. Related researches are divided into two aspects: one is the study of the stitching function of the seaming stitch [3,4]. The researchers analyzed the configuration optimization of the stitch parameters and the influence factor of the sewing fastness and comfort. ...
The influence of seaming stitches on the shielding effectiveness (SE) of electromagnetic shielding (EMS) fabric is huge, but there is not an ideal computation model for the SE of the EMS fabric with the seaming stitch at present. This paper proposes a computation model of the SE based on the equivalent seaming gap. Firstly, a structure model of the equivalent seaming gap is constructed according to the equivalent dielectric principle. The computation method of the structural size of the equivalent seaming gap model is determined by the parameters of the stitch length, number of the stitch type, needle number, and sewing thread. A computation model of the SE based on the equivalent seaming gap structure is built according to the EMS theory. The method of the correction coefficient of the model determination is given. Finally, the samples with seaming stitches are made to test the SE using the waveguide method. The computation results with the proposed model are compared with the experimental ones. The results show that the proposed model can well calculate the SE of the EMS fabric with the seaming stitch. The study in this paper can provide a foundation for further study of the influence of seaming stitches on the SE of the EMS fabric and possesses reference significance for the design, production, evaluation and related theoretical research of the EMS clothing.
... The first implementation of a closed-loop controller uses PID control, as detailed in [42] and [43]. The force applied to the fabric is varied depending on the error computed between the maximum presser-foot displacement values measured and the reference value.Fig. ...
This study describes some possibilities of setting up an adaptive control method for an electromagnetically actuated presser-foot in an industrial high-speed sewing machine. The control of fabrics feeding in sewing machines is difficult not only because of the complexity of relations between the intervening variables (material properties, sewing speed), but also because in many operations a varying number of material plies are crossed. This implies that the reference for the controller has to be adapted dynamically. Several methods, using PID and/or fuzzy logic control, have been tried and are described in this paper. A preliminary sewing test is able to provide data to tune the controller variables. With these adaptation techniques, the machine would be able to automatically adapt its feeding system according to the material being sewn.
... To analyze the performance of the feeding system, two variables are measured: Presser-foot displacement and force on the presser-foot bar.[[1],[6],[7]] ...
... The studies carried out on the feeding system have led to the development of an active actuator, as well as control methods and references for this actuation [[6],[7]]. ...
The industrial manufacturing of sewn products has always been one of the critical processes of the textile chain concerning quality assurance. Assuring the appropriate set-up and operation of all the machines, and thus the final seam quality, is a very complex task. Traditionally, this task is accomplished by empirical methods, with machine setting and quality control relying on the skills of operators and technicians. In this work, an approach to a more knowledge-based and integrated process planning and control is presented. A system was developed to measure and analyze the most important mechanical effects occurring during high-speed sewing. A general overview over this development is given in this paper.
... It uses a low-cost transducer device developed specifically for this application -with an actuator for controlling the adjustment and/or readjustment of the sewing thread tensions, as briefly reported in [5], at the beginning of operation or during the course of sewing.) Figure 1 -The overlock sewing machine including two add-on kits: (A) The electromagnetic actuated presser foot, using a proportional force solenoid placed sideways to the presser foot bar, and (B) a new thread-tensioning device. 2. THE PRESSER FOOT CONTROLLER The approach towards the development of a presser foot controller to accomplish the main objectives mentioned previously has already been published [6]. For the sake of completeness, it must be referred that this study began with the development of a software module to ease the setting of force according to the properties of the fabric being sewn. ...
... The approach towards the development of a presser foot controller to accomplish the main objectives mentioned previously has already been published [6]. For the sake of completeness, it must be referred that this study began with the development of a software module to ease the setting of force according to the properties of the fabric being sewn. ...
This paper presents a contribution towards the development of a new generation of sewing equipment integrating auxiliary add-on kits to improve performance and flexibility in the production of high-quality garments. An overview of all the recent developments concerning the redesign of the first PC-based controller developed for a novel electromagnetically actuated presser foot on an industrial overlock sewing machine will be presented. Other software modules, developed to ease the establishment of control references and the tuning of the controller parameters, as well as a brief discussion and analysis of the obtained results, will also be described in this paper. According to the latest results here reported, the presser foot firmly controls the fabric plies for a wide range of materials and situations. KEYWORDS Overlock sewing machine, fabric feeding system, electromagnetically actuated presser foot, presser foot closed-loop control 1. INTRODUCTION Market requirements for high quality products, produced from an increasing variety of materials and small-batch order sizes, stress the need for flexible and reconfigurable machines, which can be quickly set-up and/or self-adjusted. This is especially true for the garment and leather industries in European countries. To fulfil these needs, new control devices and process-engineering tools for sewing machines are required.
This work is aiming to develop a new feature to be added to the state-of-the-art sewing machines by studying the effect of the needle penetration force on the motor current. A real-time variant current drawn by the motor is recorded at a sampling rate of 3.125 kS/s. The time signal is transformed into frequency spectrum that has peaks at specific frequencies related to needle penetrating fabrics.
The proposed technique can mark out different denim fabric properties, mainly the fabric type and thickness. Increasing the fabric weight from 302.7 to 463.73 g/m² and thickness from 1 to 8 plies appear as a linear shift in the frequency peaks towards lower values within a range of frequencies between 1170 and 1300 Hz. The frequency shifts by almost −1 Hz for every 20 g/m² increase in the fabric weight while it shifts by almost −11 Hz per fabric ply increment. The correlation coefficient between the frequency shift and the number of fabric plies is calculated to be 0.998. On the other hand, frequency shifts toward higher frequency values by up to +52 Hz when different chemical treatments are applied to the fabric samples. The measured data is verified by comparing them to similar data obtained using L&M. The results of these two measurements were highly correlated with correlation coefficients of up to 0.91. The obtained results nominates that the proposed technique can be used as a real-time fabric detector for sewing machines.
The global demand for clothing has increased manifolds because of increased population, change of consumer's attitude toward fast fashion, and increase in the average income per head in many countries. This increased demand for clothing is fulfilled by the developing countries, which are now becoming the manufacturing hub for several international fashion brands. Apparel manufacturing is still a labor-intensive process in these developing countries, although there have been several automation available commercially. Availability of cheap labor and the high initial investment are the causes for which the garment industries are not adopting the technology. However, the global demand for high-quality clothing and stiff competition is now mandating many manufacturers to adopt the automation technology. This chapter discusses the global position of automation in garment manufacturing including the requirements and fundamental concepts. The major problems of automation have been discussed in detail. Automation in various processes of garment manufacturing has been covered in detail. In addition, the advantages and disadvantages of automation including the future trends have also been discussed in this chapter.
The needle thread tension is one of the important parameters which influence the quality of seam in the garment construction. Variation in needle thread tension leads to seam puckering and various other sewing defects in the garments. Presently, the tension adjustment is carried out manually by trial and errors method by the sewing operators. The research work focuses on development of a needle thread tension measuring device for Single Needle Lock Stitch Sewing Machine. The tension variation measuring device uses Pressure sensor, which is connected to the tension disc in the SNLS sewing machine, to sense and measure the needle thread tension. It measures the amount of pressure developed in the tension disc and the sensor output is fed to the control cabinet which houses electronic circuits and LED display. The maximum and minimum values of the needle thread tension for a particular sewing thread and fabric can be preselected and LED glows whenever the tension values exceeds these upper and lower control limits. Needle thread tension is varied by increasing and decreasing the stitches per inch (SPI) for the fabric selected. The work analyses influence of tension variation on different types of woven fabrics – light, medium and heavy weight fabrics. The correlation between SPI, and hence needle thread tension and fabric type is established.
