Monitoring and control of industrial sewing machines- research on thread tension behavior in lockstitch machines

Processing textile materials is generally very difficult due to the flexible nature of the material. In industries using sewing as assembly process, most processes rely on human labor, being difficult or even impossible to automate. The relations between machine configuration and adjustment, material properties, and the resulting product quality are also complex. This paper describes current work using an instrumented lockstitch sewing machine to study the dynamics and variations of one of the important process parameters during high-speed sewing of shirts: thread tensions. The objective is study the principles that may allow for an automatic setting of the machines, quality control and for real-time process control. It has been found that differences in material properties result in measurable features of the thread tension signals acquired.This work is financed by FEDER funds through the Competitivity Factors Operational Programme - COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI- 01-0145-FEDER-007136info:eu-repo/semantics/publishedVersio

Adaptive control of an electromagnetically actuated presser-foot for industrial sewing machines

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.Fundação para a Ciência e a Tecnologia (FCT

Advancements in on-line monitoring and control of parameters in knitting and sewing processes

This paper presents a summary of the developments in process control in textile processes at the University of Minho, by a multidisciplinary research group involving three different departments (Textile, lectronic and Mechanical Engineering). The studies target the automatic process parameter monitoring and control in the areas of industrial sewing and knitting.Fundação para a Ciência e a Tecnologia (FCT)

Detectarea încrețirii cusăturilor prin monitorizarea deplasării piciorului de presare

The paper investigates the relation between seam pucker, woven fabric formability, and the presser foot displacement during stitch formation. Superimposed seams of class 1 were sewn in warp and weft direction using woven fabrics for tailored garments. The presser foot height was continuously monitored during stitch formation for different sewing machine speeds. The foot displacement during the sewing cycle was correlated with seam pucker. The obtained results showed various patterns of pressure foot displacement regarding the sewing machine speeds. It was found that at a lower machine speed there is no bouncing of the presser foot and the ratio of the height of the presser foot before and after rising and declining movement versus double thickness of the fabric (h/T1), correlates significantly with the seam pucker percentage. The fabrics having a higher h/T1 ratio showed a higher percentage of seam pucker. The obtained results suggest that online monitoring of this parameter can be a useful indication of on-seam pucker appearance, providing reliable means to obtain a quality seam.Lucrarea investighează relația dintre încrețirea cusăturii, formabilitatea țesăturii și deplasarea piciorului de presare în timpul formării cusăturii. Cusăturile suprapuse de clasa 1 au fost realizate în direcția urzelii și a bătăturii folosind țesături pentru articole de îmbrăcăminte. Înălțimea piciorului de presare a fost monitorizată continuu în timpul formării cusăturii, pentru diferite viteze ale mașinii de cusut. Deplasarea piciorului în timpul ciclului de coasere a fost corelată cu încrețirea cusăturii. Rezultatele obținute au arătat diferite modele de deplasare a piciorului de presare, în funcție de viteza mașinii de cusut. S-a constatat că, la o viteză mai mică a mașinii nu sare piciorul de presare, iar raportul dintre înălțimea piciorului de presare înainte și după mișcarea de ridicare și scădere față de grosimea dublă a țesăturii (h/T1), se corelează semnificativ cu un procent de încrețire a cusăturii. Țesăturile cu un raport h/T1 mai mare au prezentat un procent mai mare de încrețire a cusăturilor. Rezultatele obținute sugerează că monitorizarea online a acestui parametru poate fi un indiciu util al aspectului încrețit al cusăturii, oferind mijloace fiabile pentru a obține o cusătură de calitate

Textile Manufacturing Processes

Textile manufacturing is an important subject in textile programs and processing industries. The introduction of manmade and synthetic fibers, such as polyester, nylon, acrylic, cellulose, and Kevlar, among others, has greatly expanded the variety of textile products available today. In addition, new fiber development has brought about new machines for producing yarns, fabrics, and garments. Textile Manufacturing Processes is a collection of academic and research work in the field of textile manufacturing. Written by experts, chapters cover topics such as yarn manufacturing, fabric manufacturing, and garment and technical textiles. This book is useful for students, industry workers, and anyone interested in learning the fundamentals of textile manufacturing

Technology Takeover and Transformation: Humans vs. Technology

When looking at the history of the fashion industry up to the present day, technology can easily distinguish the progress of fashion throughout the ages. The direction of this research is to gain insight and a deeper realization of how technology is taking over and transforming those in and revolving around fashion by slowly taking over and replacing human involvement or presence. Statistics and research show due to the adverse effects of COVID-19, technological development within fashion has seen a significant increase. COVID-19 was either the final push towards making technological ideas a reality or was the birth of new technological concepts in an attempt to reshape the fashion industry. Both those within the fashion industry and the fashion consumer must gain understanding of these technologies, lest they be left behind. This research specifically focuses on those working within the fashion industry and does not have as heavy of an emphasis on those outside of the industry. To gain an extensive knowledge on how we have gotten to where we are, this research will address fashion technologies from all angles, past, present, and future to see how it has come to have the potential to replace humans within the fashion industry

Analysis and Characterization of Embroidered Textile Strain Sensors for Use in Wearable Mechatronic Devices

Stroke and musculoskeletal disorders affect hundreds of millions of people around the world. To aid in the recovery process of people affected by these conditions, the use of wearable mechatronic devices has been proposed during traditional rehabilitation therapies. However, factor such as rigidity, increased weight, and overall bulkiness have hindered the adoption of these devices in a clinical setting. Therefore, alternative solutions in the form of soft wearable mechatronic devices have been proposed recently. This is due to these devices being lightweight and comfortable, and compliant, which makes them easier to conform to the human body. To achieve such compliance, high emphasis has been placed on the development of soft sensing mechanisms, as they are in charge of collecting information from the device, the environment and user. Among these sensing mechanisms, force and motion sensors have been extensively studied, as they are the simplest to integrate in wearable mechatronic devices. However, the majority of these sensors have been developed using soft materials that are not breathable and can cause skin irritations due to the materials used to fabricate them. For these reasons, textile sensors have been proposed as an alternative. Among these textile solutions, embroidered sensors have shown great potential, as they are relatively simple to manufacture and have high scalability characteristics. Unfortunately, embroidered sensors have the disadvantage of not being stretchable, which is one of the many characteristics of motion and force sensors. To address these issues, this thesis focuses on the design, development, characterization, and performance assessment of embroidered textile strain sensors. To this end, a framework for the development of embroidered textile strain sensors was proposed. This framework included all the necessary steps to design and fabricate these sensors. To achieve the required stretchability of embroidered sensors, a set of customizable parameters were included within this framework. Then, following the guidelines of the proposed framework, a novel embroidered strain sensor was created using a honeycomb pattern. This pattern had two main purposes: a distribution of the axial forces across the walls of the honeycomb design to protect the conductive thread; and the addition of stretchiness to the embroidered sensor. Sensors created using this pattern were embroidered onto an elastic band and then attached to a strain compensation system to increase the stretchability of the sensor further. After 50 stretching cycles, sensors showed good linearity, an average gauge factor of 0.24, an average hysteresis of 36.85% and up to 55.56% working range. This demonstrated the ability of the embroidered sensor to work as a strain sensor, without showing signs of damage and without showing signs of deformation. Lastly, a series of embroidered sensors were fabricated using a Kirigami design. These sensors were created to measure forces under dynamic conditions. Before testing, these sensors were attached to a strain compensation mechanism, which in turn was attached to a force sensing device that served as ground truth for the data collected by the embroidered sensors. The embroidered sensors were tested under three different speed profiles: slow speed, medium speed, and high speed. On each speed profile, each sensor showed high linearity, a low hysteretic behaviour, and relatively good repeatability. These results established the capabilities of the embroidered strain sensors as force sensors that could be used inside soft wearable mechatronic devices

Automation of garment assembly processes

Robotic automation in apparel manufacturing is reviewed and investigated. Gripper design for separation and de-stacking of batch cut fabric components is identified as an important factor in implementing such automation and a study of existing gripper mechanisms is presented. New de-stacking gripper designs and processes are described together with experimental results. Single fabric component handling, alignment and registration techniques are investigated. Some of these techniques are integrated within a demonstrator robotic garment assembly cell automating the common edge binding process. Performance results are reported