Hüseyin Gazi Türksoy

Exoskeleton systems are generally designed to have a structure suitable for human anatomy and are wearable structures that interact with people. They can be used to contribute to the basic functions of users such as walking, running, sitting, standing and carrying heavy loads, as well as in the rehabilitation and treatment process such as restoring the ability of the user's lower and/or upper limbs. Another area of use is to increase the strength of healthy limbs above normal. The primary goal is to increase performance and, in this sense, they have a wide range of uses. Designed exoskeleton structures make people's lives easier and provide individuals with a better quality of life in the areas where they are used. The aim of the study is to present academic studies and current products in the market in the field of wearable exoskeletons, to determine which class these products belong to, to determine which area the studies are focused on and to determine potential study areas for new research. Systematic literature analysis was used in the study and studies and products were analyzed according to inclusion and exclusion criteria. This study systematizes studies in the field of exoskeletons, determines their interrelationships, introduces basic applications for researchers who are new to this field and aims to create an interdisciplinary study area.

As consumer demands increase, environmental concerns also inevitably arise. Within the textile production chain, each processing step has its own environmentally harmful impact on nature. Every fiber, yarn bobbin, meter of fabric, chemical used, consumer lifecycle of each textile item, and recycling or waste stage of every T-shirt leaves its own footprint. Conventional natural fiber types such as cotton, wool, silk, and linen have their own environmental footprint related to their cultivation, processing steps, and consumer use. Similarly, traditional synthetic-based man-made fiber types have their own footprint in terms of raw material sourcing and degradation time in nature. Recycling in the textile industry holds paramount importance in the global pursuit of sustainability. Cellulose based recycled fibers have been preferred by the consumers lately as they provide sustainable products with high comfort and satisfying mechanical properties. There are different recycling methods currently discussed in various forums namely as "mechanical, thermo-mechanical and chemical recycling. SaXcell is a new cellulose based recycled fiber made from used cotton textiles. In the eco-friendly SaXcell process, the used cotton textiles are dissolved in a closed loop system where the water and chemicals used are chemically recycled during the process. The pulp obtained from SaXcell process is converted into fibers by lyocell wet spinning. Utilizing SaXcell based products are believed to be contributing to textile industry with a sustainable and circular production manner. This study has been performed in order to perform a comparative study for woven fabrics produced from new developed "SaXcell" yarns varying in different blend ratios in terms of some mechanical properties such as tensile strength, tear strength, seam slippage. As the results are satisfying , this study may encourage the producers and the consumers for utilizing of new developed 'SaXcell' fibre with different fibre blends which may create alternative sustainable textile products.

Hızlı moda döngüsü ve kısa kullanım ömrüne sahip düşük maliyetli tekstil ürünleri, tekstil atık miktarının artmasına sebebiyet vermiştir. Buna bağlı olarak tekstil endüstrisinin sürdürülebilir gelişimi için, katı tekstil atıklarının makul bir şekilde yönetimi zorunlu hale gelmiştir. Çalışmada farklı oranlarda geri dönüşüm pamuk (r-COT) ve pamuk (COT) harmanlarından (20/80, 35/65, 50/50, 100) Open-End Rotor iplikler üretilmiş ve ipliklerin özellikleri (kütlesel düzgünsüzlük, Uster tüylülük, hata indeksi, kopma mukavemeti ve kopma uzaması) karşılaştırmalı olarak incelenmiştir. Yapısında en fazla oranda geri dönüşüm pamuk bulunan ipliğin en yüksek kütlesel düzgünsüzlük, tüylülük ve hata indeksi değerlerine, en düşük Rkm ve kopma uzaması değerlerine sahip olduğu görülmektedir. Çalışmada farklı harmandan üretilen Open-End Rotor atkı ipliklerinden 8 tip denim kumaş üretilmiştir. Üretilen kumaşların tüm analiz sonuçları incelendiğinde, geri dönüşüm pamuk oranı arttığında atkı yönü kopma mukavemeti, çözgü ve atkı yönü yırtılma mukavemeti, bağıl su buharı geçirgenliği, ısıl iletkenlik, ısıl soğurganlık değerlerinin azaldığı, kalınlık değerlerinin arttığı görülmüştür.

This paper investigates the morphology, mechanical and thermal insulation properties of textile air conditioner dust-filled polyurethane (PU) rigid foams. Textile air conditioner dust occurs during the spinning process of staple fibres. It consists of cotton fibre impurities as boll, leaf, and short fibres that generate a vast environmental load. This dust is used as a filler and dispersed in polyurethane up to 40% wt. The cell -size of foams decreased and cell -density increased by the increase in filler ratios in which the dust acted as a heterogeneous nucleation site during cell formation. The dust agglomerated in polyurethane foam and induced irregular cell wall and hence non-uniform cell formation and many broken cells. The flexural strength and modulus decreased in higher dust content (40% wt.). The lower thermal insulation of cellulose-based dust and damaged structure/uniformity of foam cells resulted in an unstable/lower thermal conductivity of dust-filled polyurethane rigid foam composites.

The ability of being preferable in many styles has made denim fabric essential product of wardrobe. However, denim fabrics have disadvantages such as insufficient insulation, cooler sensations and liquid transfer restricting its use in cold weather due to its’ raw material and structure. In this study, dual-core weft yarn containing wool yarn as the first core and elastane filaments as the second core was used in denim production in order to improve the mentioned functional properties and provide better thermal comfort properties, especially during cold weather. The performances of fabric from dual-core weft yarns containing wool/elastane (WDC) have been examined comparatively with equivalent core-spun containing elastane (C) and dualcore weft yarns containing T400/elastane (T DC). It was concluded that fabrics with WDC weft yarns have lower thickness, water vapor permeability and higher elasticity, air permeability values when it was compared with other fabric types, which contain C and TDC weft yarns.

Dual-core yarn structures, one of the hybrid yarn types preferred in denim fabric structures recently, make it possible to improve the stretch properties of fabrics and to profit from the features of two or more materials simultaneously. In this study, innovative dual-core yarn structures containing elastane and wool yarn cores and cotton fiber as sheath fibers were developed by changing production parameters (twist, cores draft ratio). It is thought that innovative, relatively more natural denim fabrics with increased thermal insulation can produce with dual-core yarns containing wool fiber. The yarn type that meets the expectations of denim manufacturers among the 27 yarn types was selected with Multi-Objective Optimization on the Basis of Ratio Analysis (MOORA) from multi-criteria decision-making methods, and production parameters were determined. According to the MULTIMOORA method and expert opinion, 16 coded dual-core yarn sample (670 T/m, 1.05 wool draft ratio, and 3.3 elastane draft ratio) was the best alternative, and eight coded dual-core yarn sample (585 T/m, 3.5 elastane draft ratio, and 1.05 wool draft ratio) was the worst alternative found for denim fabric production.

Nowadays, denim consumers are more interested in esthetic and garment comfort features such as softness, lightweight and smoothness. Coating method is widely used to impart esthetic and functional properties to denim fabrics. It is a known fact that the coating process adversely affects various mechanical and comfort properties of fabrics. This study presents identifying of the optimum levels of the coating process parameters for combination of tear strength and stiffness properties of cotton/elastane blend denim fabrics by Taguchi method (TM) and Grey relational analysis (GRA). Denim fabric samples were coated with a standard paste used for coloring the fabric surfaces by the Rotary Screen Coating Method. The selected parameters are weft density, drying temperature, viscosity of coating fluid, squeeze pressure and fabric passing speed. First, each output was individually optimized by TM, and then all outputs were optimized together taking into account the primacy of the goals by TM and GRA. For all outputs, the most effective parameters were found as the weft density and the fabric passing speed, respectively. Consequently, optimal common combination for multi-performances was found as 14 picks/cm weft density, 160°C drying temperature, 50 dPa.s viscosity, 3 bar squeeze pressure, 30 m/min fabric passing speed.

The dual-core yarn structures, which make possible using of second core in the center of yarn has been the focus of attention for denim manufacturers in recent times. It is tried to gain different properties such as durability and flexibility to denim fabrics by using dual-core yarns. The aim of this study is to investigate the effects of twist, elastane, and wool draft ratio on the fatigue properties of dual core-spun yarns with two core materials as wool staple yarn and elastane filament. To know fatigue behavior of the yarns forming the fabric after repeated dynamic loads that is important to determine the permanent elongation that will occur in the fabric during its usage. Experimental results show that twist is a more effective parameter on elongation (before and after cyclic loading), tensile strength (before and after cyclic loading), dynamic modulus, and dynamic strain values. When core draft ratio parameters are observed, wool draft ratio is statistically significant on tensile strength after cyclic loading, elongation before cyclic loading, dynamic modulus. and dynamic strain values. Elastane draft ratio is statistically significant on the only dynamic modulus values.

Core-spun yarns containing Spandex have been widely used for the production of elastic textile materials. However, it has been encountered various problems not only during the usage but also during textile processes due to its high recovery property. In order to solve these problems, multicomponent core-spun yarns called as dual-core (DC) yarns, have been developed. DC yarns can be produced on the modified ring spinning machine in two different ways. In the first method, previously combined two core yarns are fed simultaneously, whereas in the second method, two core yarns are given separately into the centre of sheath fibre bundle. In present study, it was aimed to research the effect of these production methods on yarn features. Polyester and Spandex core components and cotton wrapping fibres were brought together in both two ways and the properties of multicomponent core-spun yarns were compared with cotton ring counterparts for three different yarn counts.